Sagan's Brain

God and the Science Classroom

2011-12-02T11:53:00.019-05:00

In a recent interview with the Nashua Telegraph, Republican presidential candidate Rick Santorum was asked about teaching creationism in schools. In a familiar tone, Santorum claimed that there is a fear, on the left and in the scientific community, of talking about God in the science classroom because of a kind of political correctness, and a sense that, in spite of its awesome explanatory power, the notion of a creator has been arbitrarily considered off-limits to inquiry. Here's his exact quote:

There are many on the left and in the "scientific community," so to speak, who are afraid of that discussion because oh my goodness you might mention the word, God-forbid, “God” in the classroom, or “Creator,” or that there may be some things that are inexplainable by nature where there may be, where it’s better explained by a Creator, of course we can’t have that discussion. It’s very interesting that you have a situation that science will only allow things in the classroom that are consistent with a non-Creator idea of how we got here, as if somehow or another that’s scientific. Well maybe the science points to the fact that maybe science doesn’t explain all these things. And if it does point to that, why don’t you pursue that? But you can’t because it’s not science, but if science is pointing you there how can you say it’s not science? It’s worth the debate.

There is, of course, nothing surprising about Santorum's argument, he's made it many times before. Science curricula are probably not terribly threatened by his candidacy -- he's polling in single digits at present -- but still, his views reflect those of a large section of our country, and the question is often posed. Why, exactly, can't God be a part of the equation when it comes to science classes?

Separation of church and state is where the conversation usually begins. And for good reason: it's a guiding principle we would probably be well advised to follow. As the founding fathers realized, governments will work better if they are decoupled from religion, because religion introduces a whole series of complications which are best avoided. We need only look at the regime in Iran to see the perils of mixing religion and government. In spite of the fact that Christian theology is largely built around peace and harmony ("Blessed are the meek, for they shall inherit the Earth," says Jesus on the mount), and other religions similarly advocate such values, terrible wars have been fought in the name of religion, and religious zealotry remains a serious threat in the world. That is not to say that religion is inherently violent... such a statement would be itself too zealous. But it is worth noting... no war has ever been fought over science, by contrast. That's because science is not an ideology, any more than math is an ideology. It has its rules and regulations, but it is a tool more than it is a system of beliefs.

What's so terribly ironic about the separation of church and state debate is that many of the people who advocate so strongly for introducing God to the science classroom are some of the same people who are so terrified of that imaginary threat of Sharia Law, which is supposedly spreading across the nation like a virus. Perhaps ironic is not the right word. Those who attack the Sharia Law straw man fail to see the connection between their desire to bring their God into the law of the land, and the (imagined) desire of their Muslim counterparts to do the same. Of course, they would counter by saying that Islam is a violent religion, one that seeks to sanction honor killings in the United States. There are obviously significant cultural differences throughout the world when it comes to what constitutes moral behavior, but there can be no doubt in this case: there is certainly no place for such brutality in a civilized society. Even so, when it comes to violence, Christianity doesn't exactly have a spotless record, either, and there's a slippery slope when it comes to theocracies. What starts as a benign attempt to create a faith-based utopia can easily become a government that demonizes, harasses, imprisons, tortures or even executes dissenters. Such things have happened many times in the history of humanity, and indeed, such things continue today in some parts of the world.

But the church and state debate is a political argument, not a scientific one. Why God really can't be in the science classroom is because the God hypothesis is wholly antithetical to the way science is performed*. Science relies on the notion that experiments can be designed, claims can be substantiated, hypotheses can be tested; and regardless of your opinions about religion, it's clear that these rules simply cannot be applied. There is no way to test the God hypothesis. There is no experiment that can be tried that will either prove or refute the existence of God, and no formula that can describe the probability of God's existence (creationists sometimes try to go the other way, calculating, for instance, the probability of a DNA molecule spontaneously falling together on its own, thereby supposing to calculate the improbability of life's genesis without divine intervention. Unfortunately for these clever apologists, these calculations are founded on a number of flawed assumptions I won't go into here).

In short, God has to be left out of the equation because God is not a variable that can be considered in any meaningful way. God, as he is usually imagined, has no mass, no length, no density or energy or anything else you might wish to measure. There's no way to quantify the God variable. But why can't we simply say that God is a sort of catch-all variable, that factors in whenever we can't get the numbers to work? Well, if we did that, we just wouldn't get anything done.

There was a time, not very long ago, when we imagined that the gods were in charge of the motions of the planets. Not in a way that we might think of it today, of course; today you might hear someone say that God created the universe and set the planets on their orbits around the Sun. But to the ancients, the planets were moving across the sky under the direct control of the gods. In some cultures, the Sun was considered a real deity, crossing the sky in a boat or a chariot. The universe was then a mystery to us, and there seemed to be no way that these objects could move amongst the stars unless there was some sort of divine hand steering them. It's not that our ancestors were stupid to come up with these explanations, it's just that humanity was groping around in the darkness for millennia, struggling desperately to make sense of a world that operates with hidden mechanisms. Indeed, modern humans have walked the Earth for many thousands of years, but it's only in the last 500 years or so that scientists like Copernicus, Newton, Galileo, and Kepler (among many others) have been able to grasp the true nature of our solar system, and by extension, the wider universe.

But suppose we had been content with our original explanation, that the gods were directly involved with the motions of the celestial sphere. Suppose we were content to say that the laws of physics simply could not be deduced, that it was beyond us, that it was simply the realm of the gods. Without a systematic way of describing the natural world, it might've been argued that the god hypothesis offers a better explanation to the question of why objects fall. Before we know the answer to that question, it's much easier to simply say, "that's the way the gods want it to work," or, "the gods made it fall." Then, as now, the intentions of the gods would have been opaque to us, and we might have been satisfied to keep it that way. After all, the planets never seem to come down out of the sky to intervene in our affairs, so what does it really matter anyway?

Well, had we not pushed ourselves beyond these mystical interpretations of natural phenomena, we would be, essentially, stuck in the Bronze Age. We would be unable to understand the mechanism behind the changing of seasons, for instance. The ancients experienced the oscillation of the warm and cold months, and figured out they could predict the seasons by observing the sky, but you need a model of the solar system to understand why it happens. Had we not given up the planet-god hypothesis, we might still run away in terror during an eclipse of the Sun or Moon. We would have no weather satellites, no communications satellites, no space telescopes, no spacecraft examining the planets up close. The window into our origins, opened for us by modern astronomy, would be forever closed to us. Without physics -- a system of describing the mechanics once thought to be the realm of the gods -- we would be incapable of these marvelous things. But the laws of physics were not handed down from on high; they were deduced with painstaking work and an unyielding devotion to the facts. Our modern world enjoys the fruits of that bold rejection of mysticism.

It can be hard, sometimes, to imagine the world that existed in the time of Galileo, when something like a heliocentric model of the solar system could be seen as a major threat to Church doctrine. The structure of the solar system seems to us today a trivial matter, hardly threatening to prove God doesn't exist. But do we not still have those who doubt, beyond all reasonableness, the discoveries of modern physics? Consider the mental gymnastics performed by creationists who simply cannot accept the central revelation of modern cosmology, namely, that our universe is billions of years old. Elaborate alternative explanations have been imagined to explain why we can see the light from galaxies billions of light years away, even though we live in a universe that is, they say, only six to ten thousand years old. Their rigid theology of Biblical literalism requires them to discount the major discoveries of physics, astronomy, cosmology, chemistry, geology, biology, genetics, and paleontology. They would rather deny the great achievements of humanity's quest for knowledge than accept that their prized book may not have all the answers.

It's true that science doesn't have all the answers, either. But with the cosmos as vast as it is, there can be no such thing as an unabridged encyclopedia of the universe. We are incapable of knowing everything, but we've certainly learned a lot, and we're learning more all the time. Science has been the key to our success, and our survival, and we do a grave disservice to our children, and those who will follow them, when we trample on the central guidelines of this precious tool. Some of our discoveries may make us uncomfortable -- as Galileo's work made the Vatican uncomfortable -- but we gain nothing by burying our heads in the sand. Better to face the world as it is than to persist in delusion.

Those who dream of injecting theology into the science classroom believe that science is just another kind of religion, eager to stifle debate and indoctrinate susceptible minds with scientific dogma. But on the contrary, science depends on debate, it thrives on it. Some of the greatest discoveries have overturned what were once considered fundamental laws of nature. But not all debates are created equal: you can debate whether the tau neutrino can really travel faster than light, for example, but you can't really debate whether the Earth goes around the Sun. We've sort of figured that second one out, and if we had to constantly re-litigate every discovery we've ever made, there would be no time for new discoveries. Individuals are welcome to challenge any theory they like, but it takes a compelling argument to be taken seriously by the community.

The evidence for an old universe, or for evolution by natural selection, is far more abundant than can possibly be described here. But the problem is, the opponents of science do not believe in its methods, so there is a fundamental disconnect. Theirs is a faith-based worldview, and it cannot be tested; therefore they imagine that science is the same thing. They imagine that scientists are just clerics of a different sort. The situation is almost certainly made worse by the epistemic closure that is especially prevalent among those who feel there is some kind of mainstream conspiracy to silence them. When we can watch our polarized news, and attend schools that teach us what we want to hear, the gap between science and religion becomes wider and more difficult to bridge. It is a troubling state of affairs.

Those who support teaching the decidedly unscientific alternative to evolution known as intelligent design often say they want to "teach the controversy." It's become something of a joke for those on the other side, an easy punchline. But it's about as good a line as any that could be market tested. It begs the question, why can't we teach the controversy? And why are scientists so frustrated if they know they're right?

Richard Dawkins, the perennial wit, has imagined a perfect analogy. It's as though you have a crowd of people who sit in a Latin class and claim the Romans never existed. Of course none of us were around to see any Romans walking around speaking Latin, but we have great ruins of their once magnificent empire, we have paintings, statues, texts, and of course, the Romance languages which survive as the descendants of Latin. It's easy to see the parallels between this and the case for evolution. The evidence is abundant, so even if none of us have ever seen these ancient people alive, the evidence that they were once alive is overwhelming. No matter, the opponents of Latin education are unmoved, and by the way, they want you to teach the controversy, so that the kids will have all the facts: some people say the Romans existed, others say they didn't. No problem!

It's clear that science and religion just cannot exist in the same classroom, any more than math and philosophy can be combined in the same classroom ("Pythagoras tells us that A squared plus B squared equals C squared... but does the triangle really exist at all? How do we know?"). Science and religion need not be diametrically opposed to each other, but they are fundamentally different things. It will take more education, not just of scientific concepts, but of the nature of science as an endeavor, if we're to break through this dreary conflict.

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Footnote:

*Note, the God hypothesis is antithetical to the way science is performed. That's not to say that religion and science must be mutually exclusive. Many theologians would argue that science and religion are perfectly compatible, and that the breathtaking discoveries of science reveal the true magnificence of God. The point here is that God is typically conceived as a supernatural being outside the boundaries of physical laws, so he/she/it is by definition beyond the scope of scientific proof or disproof.

Why Search For Life?

2011-10-19T16:46:00.007-04:00

The search for life elsewhere in the universe is among the most awesome of scientific endeavors. For the first time in the 4.5 billion year history of our planet, creatures from the Earth are now plumbing the depths of space in search of our neighbors. It is a daunting and frustrating job: the vast distances between our solar system and others, the sheer number of stars that must be surveyed, and the complicated set of circumstances required just to allow for the possibility of life on another world, make the work exceedingly difficult. Even as we have become accustomed to the idea of extraterrestrials through the science fiction of our time, and have made the most breathtaking discoveries about the cosmos, there are those who deride the search for life as mere fantasy, a waste of taxpayer dollars. Meanwhile, there are some enthusiasts who persist in the delusion that intelligent extraterrestrials are probably close-by; hiding on the Moon, perhaps, or on Mars. Such 19th-century thinking may be responsible for some disillusionment when it comes to genuine searches for extraterrestrial life, slow and painstaking as they are. In light of the fact that interstellar travel will almost certainly not happen in our lifetime, there is a kind of exploration defeatism. If the aliens are not reachable in our time, so the thinking goes, is it even worth trying to contact them?

When we truly grasp the profound void that is the ocean of space, we begin to understand the Herculean task that is the search for extraterrestrial life. The universe is far grander in scale than anyone before the 20th century ever imagined. We now know that even our fastest spacecraft, traveling at several kilometers per second, would take many thousands of years to reach the nearest star, just a few light years away. The technology to reach the stars in any reasonable amount of time is unlikely to be within our grasp for at least another century, so our best bet for the moment is long range reconnaissance. We have made some remarkable strides in this vein over the last few decades, but we still have much work to do.

Less than two decades ago we had not yet discovered even a single planet around another star, so the search for life outside our solar system seemed, in a sense, to be putting the cart before the horse. But today, through several elegant techniques, we have now cataloged hundreds of exoplanets. Exquisitely sensitive equipment has been employed to detect the minute wobbling of stars, tugged by the gravity of their planetary companions; and the Kepler spacecraft, staring at one patch of sky, has discovered almost 1800 planetary candidates by observing tiny, periodic dips in starlight intensity -- the telltale sign of transiting planets. From tens, hundreds and even thousands of light-years away, we have discovered the faint signature of alien worlds... gas giants whipping around their parent stars in a few days, and enormous rocky planets, a few of which might just have the right characteristics to support life as we know it. The results are tantalizing, the planets as exotic as they are diverse. Some scientists suggest the Milky Way alone could be home to at least 50 billion planets, and something on the order of 500 million habitable planets.

The discovery of life elsewhere in the Universe would be a defining moment in the history of our planet, a truly revolutionary breakthrough. Never again would we wonder whether we are alone; we would wonder, instead, how many others are out there. The discovery of even a microorganism on a planet or moon in our solar system, living or fossilized, would fundamentally de-provincialize biology, giving us invaluable insight into the origin of life, still one of the most compelling and contentious questions in modern science.

The signature of life in another star system, meanwhile, would prove at last that we are not alone in the galaxy, that there must be countless inhabited worlds in our universe. We might find life by detecting a planet's biogenic atmosphere, though it would be anyone's guess as to what might be there... recall that only in the last century have humans left traces of technology that could be detected from far away, meaning that biological signatures in the atmosphere of an exoplanet -- molecular oxygen, for instance -- could be alien algae, or little green men living on the cusp of their own industrial revolution.

A radio signal, of course, would be an unambiguous sign of advanced civilization. After a few billion years of isolated development, our groping in the darkness would finally begin to subside. In time we would come to know our brothers and sisters in the galaxy, and begin to bridge the great gulf between us. The vast distances between the stars preclude the likelihood of two-way communications, but we could learn much from one-way transmissions. There's no telling how much more advanced our neighbors might be. They could be hundreds or thousands of years ahead of us; indeed, there may be some civilizations out there that are so advanced that we are not even capable of detecting their means of communication -- as though we are an isolated tribe in the jungle with no telephone and someone is trying to send us an e-mail. What magnificent achievements must have been made by these advanced beings of another star, we can only guess. What mysteries of the universe have they solved? How did they survive technological adolescence? Have they found a purpose for existence? The lessons we could learn from an extraterrestrial civilization are incalculable.

But so far, there is only silence. Our galaxy is so immense -- 100,000 light years across, comprised of hundreds of billion of stars -- that there is a good explanation for having not yet found our neighbors; we are listening for the whispers of a needle in a haystack. But could there be no one out there to find? There is always the possibility, however remote, that we are the first of our kind, the first intelligent beings sending our voice out into space. But if this turns out to be true, it is also a profoundly important discovery. Instead of joining the multitude of galactic civilizations, we will have found that we are true cosmic pioneers, far more alone than we ever imagined. Where once we thought we were only carrying the torch of life on Earth, we would now be carrying the torch of life in the galaxy. A more serious responsibility is hard to imagine.

Either way, the question is clearly worth answering, and it can be answered at a reasonable cost. The excitement surrounding exoplanet discoveries, the crowd-sourcing of data analysis, and the grassroots funding for the Allen Telescope Array (a collection of radio telescopes built expressly for the purpose of searching for extraterrestrial life), all suggest that more people are taking SETI seriously. We may still have years ahead of us before we find, or don't find, what we're looking for. But things are looking up.

Juno sends us another Pale Blue Dot

2011-08-31T11:03:00.014-04:00

The Juno spacecraft, recently launched on its 5-year voyage to Jupiter, just snapped this picture of the Earth-Moon system from a distance of 6 million miles. What a lovely and vulnerable pair.

It's worth quoting Carl Sagan:

"That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there--on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known."

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You may have noticed a dearth of postings recently. I'm afraid it's been a busy summer, and will likely be a busy fall. In light of this, some postings will be shorter than has been typical of late, but hopefully I'll be able to write a little more often this way. I hope you will continue to find the content satisfactory. In the meantime, be sure to follow me on twitter.

Farewell to the Shuttle

2011-07-08T11:58:00.010-04:00

Today the space shuttle launched on its 135th and final mission. When the four astronaut crew of Atlantis arrive back on Earth just two weeks from now, a complicated chapter in human spaceflight will draw to a close, and then, for better or for worse, we will have plenty of time to ponder its place in history.

For the next several years, American astronauts will have to hitch a ride aboard Russian Soyuz rockets to visit the space station largely funded by US taxpayers. In just two weeks, Russia will become the only nation on Earth in the business of launching humans into space. But after a few more years, hopefully, Americans will be flying into orbit atop commercial spacecraft, and NASA will be well on its way toward the goal of sending human beings far beyond low-Earth orbit, to an asteroid, and eventually to Mars and its moons.

But the future of manned spaceflight is by no means written, and the legacy of the space shuttle's successes and shortcomings looms large. Conceived during the Apollo era, finally launched for the first time in 1981, the space shuttle never quite lived up to its promise of routine spaceflight. It was a technological triumph -- an elegant, reusable space plane capable of delivering large payloads and even retrieving spacecraft to bring back to Earth. But in a way, the seemingly unadventurous nature of its work sapped the energy out of America's appetite for space exploration. The higher-than-expected costs, and the tragic loss of two crews in 1986 and 2003, made us question whether the whole endeavor was really worth it. Even as the shuttle's unique capabilities allowed us to service the Hubble Space Telescope five times in Earth orbit, and delivered many sections of the now magnificent International Space Station, the shuttle program came to be seen by many observers as a waste of time, a holding pattern of sorts. We had made some daring ventures into the abyss, landing 12 men on the Moon, and then we spent 30 years orbiting the Earth, again and again and again and again.

To say that flying the shuttle was not a daring enterprise is a step too far. Spaceflight of any kind is an extraordinarily complicated venture, where the slightest malfunction can result in catastrophic failure. The Challenger and Columbia disasters are a testament to the true hazards of human spaceflight. But with the advent of the shuttle program, NASA's mission slowly diverged from the dreams of its financiers, and in failing to hold the imagination of the public, what was arguably the main driving force behind human spaceflight -- the itching desire to explore the frontiers first hand -- withered with each successive flight.

By and large, in the 1960s America was not terribly interested in geological discoveries on the Moon. The Apollo program was not really about science, and for most people, the science was probably of tertiary concern. Politically it was about beating the Soviets, for sport and for security, but viscerally, we recognized its deeper meaning. To walk on the Moon, that rock that has circled serenely above us for billions of years, never once lighted upon by creatures from the Earth, was truly a moment for the ages. Never again would it be an untouched world, forever would it bear the footprints of humans. It was arguably the crowning achievement of human technology. But after only 6 successful landings, we pulled back to plan our next move. The Russians were working on space stations, so we had to get into that game, too. In a sense, the very thing that had driven us to such great heights in the age of Apollo -- competition with the Russians -- drew us back to spend the next three and half decades orbiting the Earth. Meanwhile, dreams of a rapid expansion of space exploration, with moon bases and Mars landings, largely evaporated.

Still, the space shuttle was and is the greatest vehicle ever built for low-Earth orbit operations. But perhaps it was always doomed to live in the shadow of Apollo. The splendid optimism of space exploration in the 1960s, the breathtaking speed at which we achieved our goals, the seemingly limitless possibilities, gave way to the static pessimism and cutbacks of the 1970s and 1980s. Perhaps Apollo was just the high that we could never hope to achieve again.

In spite of all this, I will miss the space shuttle. It has served us well, and the 355 brave astronauts who have flown on the shuttle have done important work -- conducting a host a valuable zero-gravity experiments, launching interplanetary spacecraft, repairing satellites, and ushering in a new age of international cooperation in space with the Mir and ISS programs. But the shuttle's retirement is a necessary part of moving on to the next mission. If there is something to lament, it should not be the end of a program that by any standard has gone on a bit too long; rather, it is the wide gap between STS-135 and the launch of the next manned American space vehicle. That remains four or five years away, and the way forward is a little murky. Funding for manned space flight is in limbo, though it always seems to be. But as Congress wrestles with the White House over the money and the mission, we will cool our heels while Russia takes our astronauts up at $63 million a ride. Perhaps we will feel the itch again in the meantime.

The so-called Commercial Crew program seems to be the right way forward. If we are to make manned orbital flights truly routine, as we should hope they will be one day, commercial operations are the next logical step. The resources at NASA are to be refocused on missions beyond the Moon, to an asteroid in 2025 and to Mars in 2035. There's good reason to suspect those dates may slip, as firm deadlines don't seem to mean quite as much as they did in the 1960s. We have set our sights on new horizons, but it will take sustained effort to meet those goals. Spending the next four or five years languishing without a manned space program of our own may frustrate the public just enough to renew our desire to explore.

At first glance, the time frames involved with going to an asteroid and eventually Mars may seem terribly timid. But we should not forget that going to an asteroid, let alone Mars, will be a spectacularly difficult exercise, for which we are just beginning to design serious plans. The Mars landing, recently described by The Economist as the "El Dorado of space exploration," will require preparation and design of unprecedented sophistication. We have not yet even managed a robotic sample return mission from Mars. Sending astronauts across the interplanetary gulf separating Earth and Mars will be far more dangerous than crossing the mere quarter-million miles from the Earth to the Moon. In fairness to NASA and the shuttle program, dreams of a Mars landing very shortly after Apollo were probably far too optimistic.

So, here we are. Will we press on to greater voyages, sending out at long last our cosmic argonauts to plumb the depths of interplanetary space? Or will we wait for the next generation to pick up the mantle we have borne just a little way from where we started?

Time will tell. In the meantime, we say farewell to the space shuttle. Good luck, Atlantis.

Still Here

2011-05-23T12:15:00.008-04:00

Well, good news. We survived the rapture. Or rather, we survived saturday.

It turned out to be a pretty nice day, actually. I was invited to three rapture-themed parties, and we all had a good laugh about the May 21st doomsday prophecy of Harold Camping, the 89 year old charismatic responsible for the apocalyptic prediction. Between the throng of Camping's followers spreading the word around the globe, and the habitual jokesters of social media reveling in the absurdity of the prophecy, it made for quite a phenomenon.

But in the wake of this mirthful saturday, Camping's followers face a brutal reality. Some have alienated their families, others have left their jobs, still others have liquidated their assets to warn the world of their imagined catastrophe. Many of us have wondered what we might do if we knew the world were coming to an end. In Camping's followers, we have some experimental evidence. And the question now is, what's next for these disappointed followers? Will they lose their faith in Camping? Will they lose their faith in God? Or will they delude themselves into thinking that somehow the events of saturday (or more accurately, the non-events of saturday) are some kind of confirmation for their worldview? No doubt reactions will be diverse, but it will be interesting to watch. There have been many religious leaders who have predicted the end of the world, but few have gained so much traction as this one. Where many apocalyptic groups have lived on secluded compounds, Camping has managed to foster a global following.

But how could such a prophecy capture so many minds? Why are people so willing to trust in these sorts of far-fetched scenarios, when the same people are so dubious about scientific findings backed up by massive amounts of evidence? That question may be too large to answer here, but we can tease out some explanations.

The most obvious explanation is fear. The end of the world is a very scary idea, especially when we imagine it to be at the hands of God. There is no escape from God's wrath, and the certitude of the True Believers is enough to give anyone pause. But of course, the doomsday prophecy also offers salvation. If you pray hard enough, do enough good, tell everyone you know to repent, you might be chosen to ascend to Heaven while the rest of the Earth is consumed in unimaginable turmoil. Sounds like a no-brainer. Even if you have some doubts, you might as well take Pascal's Wager, and try your best to be one of the chosen.

Undoubtedly, Camping's followers are somewhat in the dark about the history of doomsday predictions. There have been many over the years, and so far the doomsday soothsayers are batting zero. Camping, as you might imagine, has dismissed all the other attempts to predict the end of the world, deriding their methods as bogus. But his so-called calculations are the ones we should really follow (and never mind his own failed doomsday prediction back in 1994). Perhaps Camping's followers are bamboozled by these supposed "calculations." They may not have believed Camping was actually conversing with God, but if you arbitrarily assign numbers and values to cherry-picked events in the Bible, tie them together with esoteric numerology, all of a sudden that sounds like science. And who can doubt a science-based reading of the Bible? Interestingly, these True Believers are likely skeptical of real science (Camping himself is a young-Earth creationist), but they are perfectly happy to use scientific-sounding arguments to back up their own beliefs about the Bible.

It's difficult to determine just how many people took Camping's prediction seriously, but there must have been several thousand at least. Camping's organization is worth as much as $80 million by some estimates, funded by the contributions of his fervent supporters. We can feel sure that they represent a tiny percentage of the American population, but what sets them apart is not an obsession with the apocalypse, but merely the idea that the date of the apocalypse can be discerned from Biblical numerology. Consider this astonishing statistic: according to a recent Pew Research Poll, 41 percent of Americans believe Jesus will return to Earth by 2050. You read that right.

A number of questions arise from this astounding figure. What does that say about the percentage of American Christians who have embraced End Times theology? It turns out about 54% of American Christians subscribe to this worldview. What are the political views of this group? How do they feel about nuking Iran? Are they concerned about global warming? Do they think gays are evil? Do they believe in science? And why will Jesus return by 2050? What evidence is there that He will come in this lifetime, versus say, 2075, or 2100? Or 3100?

Many End Times believers will cite a foreboding sense that things are really starting to fall apart now. All the floods, earthquakes, wars, etc. Well, maybe they're on to something. It's strictly anecdotal evidence, but perhaps we really are seeing an uptick in natural meteorological disasters. After all, increasingly violent storms are a predicted result of climate change. But are things really worse than they've ever been? I wasn't around in the 1960s, but I would guess those were some pretty scary times. We faced a real apocalypse during the Cuban Missile Crisis. Let's also not forget the threat of Germany and Japan in the 1930s and 1940s. The fate of the world really did hang in the balance during World War II. So why do people think things are falling apart now? Well, it's a safe bet that we're more scared by the things that actually threaten us than the things that threatened our ancestors. Hitler threatened to take over the world, and succeeded in conquering most of Europe, but he's not too scary to me here on the other end of 66 years.

Even so, we do face significant challenges in the 21st century. Climate change is real, and it has yet to be addressed adequately. Nuclear weapons remain a serious threat to the survival of humanity, and it's clear that the obsession with nuclear weapons as a national status symbol has yet to subside. We are facing energy and food shortages as the population continues to expand. But for those who expect to be magically lifted into Heaven at some date in the not-so-distant future, these problems may not be of much concern. Today the Middle East is a hotbed of violence, and tensions over Israel remain high. But for 41 percent of Americans, that may be good news... according to the prophecy, this is all leading up to the return of Christ. Maybe we should help these developments along.

So, maybe Camping's followers were just a fringe element, and we shouldn't pick on them too much. But End Times theology remains a major force in the United States, and it has some disquieting implications.

In spite of a certain satisfaction that comes with failed prophecies, and the relief of having a regular day on May 21st, I feel badly for Camping's supporters. In blindly following their teacher, they have turned their lives upside down. It seems likely that they have been poorly educated. As for Camping, it's hard to know whether he really believes what he's been preaching, or if he is just the latest in a long line of charismatic con artists. But his followers just longed for salvation, and feared for the lives of their loved ones. They may have been misguided, but their intentions were good. And in 2011, it is not difficult for people to consume bad information. The polarized news channels, the niche media outlets, the proliferation of the internet, and irresponsible programming from seemingly trustworthy sources, all make it very easy. Pseudoscience is everywhere, and it can spread like wildfire.

Anyway, I'm glad we're all still here.

On Earth Day, Dreaming About The Future

2011-04-22T09:51:00.014-04:00

Photo from the Galileo spacecraft, 1990.

I grew up with dreams of a dazzling future. As children of the 20th century, I'm sure most of us did. The future of my imagination had computers you could talk to, fabulous portable electronics, video phones, virtual reality, and people living in space. Indeed, some of those dreams have become a reality. In our time we have seen some remarkable technological advances -- the explosion of the internet, the dizzying leaps in computing power, the ubiquity of powerful personal electronics, and breathtaking discoveries in medicine, astronomy, and cosmology, for instance. In spite of recent economic stagnation, there is the persistent sense that our best days are yet to come. The future of our dreams holds untold technological wonders.

This future, of course, is predicated on the consumption of power. Lots of power. The technologically sophisticated lifestyles we have come to enjoy will require an unending supply of energy, on an enormous scale. In 2005, the United States alone consumed about 100 quadrillion BTUs, roughly the energy contained in 800 billion gallons of gasoline or 3.6 billion tonnes of coal. Annual world consumption is on the order of 450 quadrillion BTUs, and with the world population climbing ever upward, it's easy to see that the demand for energy will continue to swell.

But there's a problem. Our power consumption is responsible for an obscene level of carbon emissions which threaten to alter the climate of the Earth, causing violent storms, coastal flooding, the destruction of ecosystems, the acidification of the oceans, and the widespread extinction of many species, which may have a profound impact on the food chain. Fueled mainly by coal, oil and natural gas, this level of consumption is unsustainable at best, and extraordinarily reckless at worst.

On Earth Day, much is made about the need for conservation. Not only should we recycle and do what we can to minimize pollution, but we should also cut down on our energy consumption. That's a great idea, and in 2011, that's what you must do if you're serious about saving the planet. At a time when there is heartbreakingly little political will to make big changes in our energy economy, the only way to reduce our environmental impact is individual responsibility. Earth Day is an important part of spreading that message, making sure people know what they can do to make a difference, but it may do little toward convincing the millions of Americans who are decidedly hostile toward environmentalism. And so, even if every environmentalist in America were to minimize their carbon footprint, half of the population might persist in unchecked consumption.

What is troubling about the energy conservation message, and what is understandably so unattractive to those on the right, is the austerity.
We are told to turn off our lights when we leave a room. We should unplug everything when not in use. But for myself, I don't want to turn off the lights! I would prefer to have every light on when I'm at home in the evening. But if I'm going to be serious about the environment, I have to knock it off. Adding to the frustration is the sense -- familiar to any voter -- that the actions of one single person cannot have much of an impact. If I'm extremely responsible about my energy consumption, it still doesn't feel like I'm changing anything... the carbon dioxide in the atmosphere continues to tick upward. And of course the opposite is also true: If I'm terribly irresponsible when it comes to the environment, it doesn't really feel like I'm doing much damage. After all, I'm just one person, and the world is very large. But the reality is, you're either a small part of the problem, or a small part of the solution.

But austerity is not how I imagined the future. None of us dreamed of a future in which we have all learned to be extraordinarily frugal with our energy resources. We have dreamed of flying cars, faster airplanes, bigger televisions... but that future will require lots of energy. We might imagine a world where recycling is as routine as brushing your teeth, where saving energy is as natural to us as closing the window on a cold day. But the inhabitants of the future will not be super-beings, miraculously trained in the ways of environmentalism at some unknown time between now and then. No, they will be us, and they will be our equally fallible progeny. We would be foolish to count on a sea change in personal responsibility.

That's why I believe the government has to intervene in some way. We just can't hope to get all the way there with personal responsibility, and austerity is just not a long-term solution. But with an energy economy based on clean, renewable sources, we would not have to worry nearly so much about our carbon emissions. We could consume energy more-or-less unselfconsciously, and I suspect that's an idea America could get behind.

Undoubtedly, the biggest investment would be the energy production itself. We should not waste much time with technology that seeks to convert corn into fuel; the process simply consumes too much energy to start with. The yield is too low, and the carbon emissions of production ultimately make the technology insufficient for our needs. On the other hand, we have a collection of simple, elegant solutions available to us: harness the power of the wind, the power of the Sun, the power of the waves. None of these on their own are a perfect solution, but together they represent the best answer to solving our energy crisis. There is an infinite amount of power available from these sources... we are only limited by the number of generators we can build. There is no need to mine, drill, or grow; we can simply harvest the abundant energy of nature. Some of the technology is not yet cost competitive, but it could be, given a leg up.

There's a funny thing about technology: as it ages, it becomes much cheaper, but it is obviously no less sophisticated. A typical VCR in 1986 might have set you back about $300; adjusting for inflation, that's almost $600 in 2010. But a VCR/DVD combo, purchased in 2010, might cost you as little as $60. It's not that VCRs are 10 times easier to produce now than they were 25 years ago. Instead, market forces have dictated the price. The point is, there is nothing inherently expensive about most of our clean energy alternatives. Rather, they are simply not quite as cheap as they could be, because they are still comparatively rare. The one exception to this is solar power... most photovoltaic cells are made from rare Earth materials, so they cannot be made much cheaper. But we can feel sure that in time, given enough support and demand, wonderfully imaginative ways will be found to create these materials synthetically, or something far less expensive will be found to work almost as well.

Of course, it would be difficult for entrepreneurs to start clean energy companies on their own. But since it is in the best interest of the nation, the government would be well advised to invest. We can imagine an arrangement whereby the government fronts much of the initial cost to install a network of clean energy production sites, and then the coal, oil and natural gas companies could buy the government out over time... not unlike the very successful rehabilitation of American car companies in 2009. In this way, these corporations would not be put out of business by the government. Rather than stifling growth and passing unfunded mandates, the government would be able to steer the energy economy in a direction that benefits all parties, and allow the private sector to take over gradually. A partnership between government and business, benefiting the public at large, is essentially what both parties want anyway. The companies could remain the nation's chief energy suppliers, and the historical opposition to their product would fade away. And it would make good sense for these companies to take the deal... as time goes on, fossil fuels will be more difficult to access, and as the effects of climate change become more apparent, public opinion could force them out of business altogether. Other nations are now moving to get in on the clean energy revolution, so the United States would be wise to get ahead of the market while it can. The time is now to start moving on building a clean energy economy. The plan I've outlined may be flawed in some way, as the situation is far more complex than can be summed up in a few paragraphs. But the point here is not to advance a particular idea, so much as to emphasize the need for novel approaches to the problem. We need a lot more people thinking boldly. We need imaginative solutions.

Reducing energy consumption in the short-term remains critical. The transition to a clean energy economy won't happen over night, so we will still rely on fossil fuels to bridge the gap. But beyond personal responsibility, higher efficiency standards can play a big role here. The solution would seem to require little in the way of government spending. We need only be brave enough to tell the corporations that their products will have to be a little more efficient if they want to sell them in the United States. Efficient windows, light-bulbs, appliances, automobiles... these changes need not put too much strain on the market. If every company has to play by the same rules, there should be no major fluctuation in the market dynamics. Besides, the American demand is not going away. So long as there are Americans, there will be companies itching to sell to them. And if efficient products are the only ones available, that's all that will be used. I can no longer choose to purchase leaded gasoline. It was taken off the market, and we are all better for it. Any tremors in the market caused by higher efficiency standards should dissipate quickly, and they would be a small price to pay for securing the energy future. Instead of fearing the economic consequences of doing the right thing, we should focus on finding ways to make sure doing the right thing is economically productive.

President Obama has proposed that 80% of our energy come from clean energy sources by 2050. That's a step in the right direction, but if history is any guide, this goal will be adjusted, watered down, or downright abandoned in the coming years. It will take sustained effort to see all of the necessary changes through to completion. There are powerful interests that would like to maintain the status quo. But these powerful interests are more concerned with short-term profits than long-term viability, and it is the job of the government to temper the needs of business with the needs of the people. In a time of economic downturn, there will be those who say we cannot afford to make big investments. But some people will never be on the side of government solutions. And I, for one, have a hard time imagining a better investment.

Earth Day is about spreading awareness, and that is crucial in 2011. There can be no serious plan put into place until there is the political will to do so, and we know that the political will follows sluggishly behind mainstream opinion. We will have to evangelize for science. We will have to educate people on the real dangers of climate change. In the 21st century, we are used to having pills to take for any ailment. We are vigilant when it comes to our own health. But there are no magic pills to maintain the health of the Earth, and we have ignored the symptoms for too long. We've got to save the planet if we're to see the future of our dreams.

The Clarity of Embarrassment.

2011-04-08T09:39:00.011-04:00

Yesterday I sort of embarrassed myself in front of thousands of people in the twitterverse. It might not have been such a big deal, but it was a lapse in critical thinking, and since this blog puts a lot of emphasis on skepticism, I couldn't help but feel like a fool.

Let me explain. Yesterday, Richard Wiseman, author of an excellent blog featuring fantastic optical illusions and puzzles, posted a irresistible magic trick on his twitter page. He invited readers to select one of five cards -- as he labeled them: 9C, 2H, 5C, 7D, and 10S -- and then he asked you to click on this link to see if he guessed it correctly. Try it now... did it work for you?

Well, it worked for me. Just like any other magic trick, I knew there was nothing supernatural about it, but I assumed that there was some kind of trick that allowed him to make the prediction. After all, he got my card right, and I've seen plenty of other tricks in a similar vein -- number tricks, and various other word games that almost always get the right answer. Perhaps it was some kind of statistical phenomenon, I thought, whereby people almost always select the 2nd of five options. Or maybe it was that people tended to prefer its placement on the page, which he must have chosen strategically, or maybe people tend to like the letter "H" more than the others. I couldn't see how it was possible, but as with many other things in this world, that didn't mean there wasn't an explanation. I felt that there was one. On his twitter page, Wiseman said he was getting an excellent response from the twitter card trick, and he was going to share a few of them. Perhaps eager to expand my own readership, I responded with an enthusiastic endorsement of the trick, and to my surprise, he shared it with his 75,000 followers just a minute later.

Within a minute of my first message, I qualified it with another: there is, I said, a built-in 20% chance that he'll get the card right by coincidence, but I thought that there had to be more to it than that. Well, in just a few more minutes, a number of clever folks were taking shots at my intelligence. I immediately realized my oversight.

I hadn't questioned my assumptions. Why would there have to be more to it than a 20% chance of getting the answer right? He's not performing in front of an audience, so he's under no pressure to get the answer right, and there's a certain opaqueness about twitter that allows one to highlight messages you like and keep invisible the ones you don't. So all he needed to do was bamboozle a few people, and share their testimonials. I hadn't seen the comments of the 80% of people who tried it and did not have their card predicted correctly. It was a classic experiment: between me and many other tricked readers, it demonstrated our willingness to be fooled, our talent for imagining elaborate explanations, and our tendency to record the hits and ignore the misses.

This is, of course, a well known phenomenon. When I play roulette, my odds of winning are just about the same every time I play. But if I'm feeling lucky while I'm playing, I may take more notice of my wins than my losses. And just the opposite is also true; if I'm feeling unlucky, I may take more notice of my losses... and of course in either case, my suspicions are confirmed, and I seem to have some evidence that the universe is on my side, or is conspiring against me. Indeed, this sort of thinking is pervasive, and it's hard to set aside. Some people are chronically at the mercy of an insidious cosmos. When we harbor ill feelings toward another group of people -- another ethnicity, nationality, political party, etc -- we have a tendency to catalog in our minds all of the evidence that supports our prejudice, and forget about all the evidence that contradicts us. When we adhere closely to a particular theology, we may call good things that happen "blessings," but we may be unable or unwilling to attribute the bad things to the benevolent deity we imagine God to be.

We can all be fooled sometimes. As much as you might strive to think critically about the world, sometimes it doesn't take much to make you throw your skepticism right out the window. It doesn't matter that I knew it wasn't "magic." I realized quickly enough that there was a 1-in-5 chance of success regardless of whether there was anything else at play, but it took longer to accept the fact that the trick was perfectly ordinary, that there was nothing special about it except that I happened to be in that 20% of people who just by accident saw evidence that it was more than just chance. We are often unable to see beyond our own narrow frame of reference, so that with just a single trial (your experience), you might deduce that there is a complex system at play, rather than simply a high probability of having that experience as the result of pure chance.

Our interpretation of the world can be similar in just about any circumstance. We see the Earth and the universe as perfectly suited for harboring lifeforms like us, so we may conclude that it was designed with us in mind. Of course, many cosmologists think there could be any number of other universes, and any number of different properties for the physical laws of nature. But it's easy to see that beings capable of contemplating the universe are only going to exist in a universe where those beings are permitted by the laws of nature. It's a bit like speculating on your purpose for being alive at this moment. You might wish to think that there was a special, predetermined chain of events that led to your conception and birth, but what about all of your potential brothers and sisters that never made it through the barriers of birth control? They cannot attest to any special purpose, because they never existed. We may feel like there has to be some spiritual director of the great cosmic drama, but the universe is under no obligation to adhere to our preferences. The universe is a place rich in mystery and wonder, but in terms of any alleged purpose or design, the truth could be more ordinary than we want to think, or more ordinary than it feels. We are prone to deducing design where there may be none.

Insomuch as this was an embarrassing moment for me, I would love to just delete my tweets and not highlight this little incident. But science has got to be bigger than that. We have to be brave enough to admit when we are wrong. And in any case, embarrassment is not all bad. We need it to learn valuable lessons. I've learned to be careful about what I say, largely due to the countless times I've gotten egg on my face for not doing so. Those lessons go a long way toward making you a better person, but as we saw yesterday, it's no guarantee against making mistakes in the future. The lesson here, of course, is that skepticism has a marvelous way of helping you to not make a fool of yourself. If you can approach the world with a critical eye, you're more likely to avoid a twitter pile-on. And believe me, it smarts.

Follow on twitter.

Skepticism!

2011-04-02T15:22:00.000-04:00

In case you were wondering, yesterday's post, "The Awesome Implications of Narwhal Telekinesis," was just an April Fool's joke. I hope you enjoyed it.

The Awesome Implications of Narwhal Telekinesis.

2011-04-01T10:27:00.011-04:00

In case you missed it, there's BIG news in the world of cetology. Dr. Sven Sorensen of the Danish Research Institute for Whales, Dolphins, and Porpoises, has just announced a finding that will fundamentally alter our perception of our mammalian cousins in the sea. NOAA is providing updates as they become available, be sure to follow them here.

Since 1988, Dr. Sorensen has been the world's leading expert on the narwhal, a tusked whale native to arctic waters, resembling something like a beluga crossed with a unicorn. These fascinating creatures have remained somewhat of a mystery until recently, when Dr. Sorensen made a startling discovery. You see, we've always known that whales are smart. As mammals, they teach their young as we humans do, they engage in play and even problem-solving. But no one could have expected what Dr. Sorensen has just discovered.

It turns out that narwhals have a kind of telekinesis, seated within the R-complex of their brains! It sounds like science fiction, but some scientists have long suspected that there might be some sort of biological connection to the quantum world around us. Dr. Robert Lanza, author of the incomparably illuminating book Biocentrism, argues that life controls the Universe, that the Universe could not even exist without a biological medium, something that could give it some kind of purpose. Many skeptics have shunned Dr. Lanza's work, but now it seems he may have been right all along.

To understand the nature of the narwhal's telekinetic abilities, we would want to examine what it is the whales might need it for. For many years, narwhals were thought to use their giant tusks as a kind of ice breaker, for making holes in the arctic ice sheet so that they can breathe. Well, Dr. Sorensen has now discovered that narwhals actually manipulate the ice sheet with their minds, moving them about by sheer thought, and contrary to the prevailing hypothesis, the tusks may simply be used to boast to other whales about their mental faculties. New research suggests that narwhals can sometimes exhibit jealous behavior, and in a violent conflict between two males, one might actually toss the other onto the ice above, where the whale might die of extreme cold and inability to return to the water. Indeed, several narwhal carcasses have been discovered on the ice in recent years with no apparent means of getting there. It now seems clear that in the midst of whale combat, fighting over a female perhaps, they might actually be tossed around by their opponent's telekinesis, sometimes up to 20 or even 30 meters.

But perhaps more important than what this new discovery tells us about the narwhal are the incredible implications for our own brain power. It's just in the preliminary stages, but Dr. Sorensen and his team at the DRIWDP are working on finding a way to isolate the functions of the narwhal brain and see how we might apply it to our own brains. In other words, if they can figure out how the telekinesis works, they could extrapolate that knowledge to figure out how we might employ this little trick for our own benefit. Think of the possibilities! With just a little tinkering in the deepest recesses of our brains, where our inner crocodile lurks, we might be able to control our computers with our minds, do our yardwork without leaving the porch, and just maybe, hug our loved ones from far away. It's too soon to say for sure, but we may be on the cusp of a new revolution in brain power.

Of course, this power will come with awesome new responsibilities. What might we do on the subway, with people jostling about and tempers flaring? Could our newfound faculties give us superhuman strength that we might use to combat our irritating neighbors? And who will get the technology? As it is a Danish state organization, the DRIWDP is under no obligation to share its findings in detail outside of the country. This could turn out to be a blessing and a curse. You see, we're getting into a realm of what you might call "dangerous knowledge." What if our enemies figure out how to crush our tanks with their minds? What if they get the technology before we do? Could there be entire battles fought with just the force of our brains? And just how much power could we attain with just a little tweak in the wiring of our brains? It's easy to see how such a situation could lead to a new kind of brain-power arms race. If the Danes keep the knowledge to themselves, the world might be a little bit safer, but then again, they alone might possess the technology and become a fearsome force in 21st century Europe.

It will be critical that we begin our own investigations of the narwhal's uncanny abilities, and we can be sure the United States will be undertaking this major project in short order. But we must be careful about what we let out of the box... once this sort of power is unleashed on the world, there will be no going back. The narwhals have lived more-or-less peacefully, because whales are gentle creatures, far more intelligent than we give them credit. I'm not so sure we humans are ready to handle the responsibility.

The MESSENGER Mission

2011-03-18T17:05:00.027-04:00

Last night, as much of America was tuned in to the drama of NCAA basketball, I was delightfully disinterested. I knew there would be lots of other games in store, and I just couldn't miss the big event. At 8 o'clock eastern time, NASA television carried live coverage of the MESSENGER orbit insertion maneuver, which was to be the first time any spacecraft has ever orbited the planet Mercury. It was a critical moment for the mission -- perhaps the most critical of its 6 1/2 years in flight -- and there was only one chance to get it right. Had the OIM burn failed, the spacecraft would have whizzed by Mercury, perhaps never to return. Fortunately, the maneuver seems to have been a total success.

NASA television is not the most glamorous coverage you can imagine, but it's not bad either. The production values are not incredibly high, but there are no commercials, and you get to enjoy an unfiltered look at our space operations. There was, of course, no live television images broadcast from MESSENGER, so the coverage consisted of interviews, animations, slide shows, and a live feed from mission control. The interviews were fascinating, but they're sort of staged for the sake of coordinating footage, so it can feel a little awkward. Even so, I didn't mind. After all, I thought, I would much rather have more money be directed to the missions themselves than to waste money on the bells and whistles that go into a really slick television show. Still, I wondered how many people were watching, and how many more people might watch if NASA were a little better at showing the public just how incredible their work really is. MESSENGER is great mission.

The last time Mercury was visited by any spacecraft was in 1975, when the Mariner 10 spacecraft made the last of its 3 flybys. Mercury is too close to the Sun to be observed by the Hubble telescope, so if we want to get a good look at it, we have to send a spacecraft. But because it orbits in such a hostile region of space, any spacecraft bound for Mercury must be engineered to deal with extreme temperature fluctuations; there is an almost 1100 degree Fahrenheit difference between light and shadow. Mariner 10 provided us with a lot of great science... among other things, it discovered that Mercury has a magnetosphere, totally unexpected amongst astronomers. But due to the timing of its flybys, and the nature of Mercury's slow axial rotation, it was only able to photograph about 45% percent of the surface of Mercury. The rest would remain a mystery. There would have to be another mission -- an orbital mission -- to map the rest of the planet, and answer some of the questions that were raised by the tantalizing results of Mariner 10.

For many years, another Mercury mission was not reasonable. It just cost too much, and there were lots of other places we wanted to go. Part of the problem with going to Mercury is that, contrary to what you might think, it takes a lot of delta-v to get there. Unlike missions to the outer planets, which have to muster up enough speed to climb away from the Sun, a trip to Venus or Mercury is falling toward the Sun, so you might expect that this requires relatively little propulsion capability. But remember, gravity is an accelerating force, so if you fly straight toward the Sun, you're going to pick up a lot of speed, and you would need an obscene amount of propellant to slow the spacecraft down to go into orbit. Mariner 10 was able to rendezvous with Mercury using a gravitational assist at Venus to slow it down and alter its trajectory to intercept Mercury (in fact, Mariner 10 was the first interplanetary spacecraft to use gravitational assists). But even then, Mariner 10 was incapable of orbiting Mercury.

MESSENGER's orbit maneuver was made possible by a complex series of gravity assists. The distance between the orbits of Mercury and Earth is only about 57 million miles on average. But as of yesterday, MESSENGER had traveled a total of 4.9 billion miles! That's almost 53 astronomical units... much farther than the distance to the orbit of Pluto. This is because MESSENGER spent 6 1/2 years traveling to Mercury, making almost 15 laps around the Sun: 1 flyby of Earth, 2 flybys of Venus, and 3 flybys of Mercury before finally approaching at such a speed that it could rendezvous and insert itself into orbit around Mercury. And even then, the insertion maneuver consumed 31% of the propellant carried at liftoff, leaving just 9% in the tank.

MESSENGER is a Discovery-class mission, which means it was made as cheaply as possible. But the gravity assists were just one way of saving money. To save additional propellant, the spacecraft also used its solar panels to make fine adjustments to its attitude and trajectory by using the radiation pressure of the Sun. Just like a solar sail, MESSENGER's solar array pivoted this way and that to use the winds of space to conserve energy. The spacecraft also needed a sunshade to keep its sensitive equipment cool, so the engineers gave it a heat shield made of ceramic cloth!

Sometimes, I think, we forget about Mercury. It is the innermost planet, and it is a scorching place, but it has no moons and no complicated atmosphere. It looks a lot like our own Moon, so maybe we feel like we've already sort of gotten all the information that we need. It certainly doesn't have the violent, morbid appeal of Venus, nor does it seem nearly as inviting as Mars, and compared with the giants of the outer Solar System, it may be a bit of an afterthought. But in spite of its relative proximity to Earth, we know so little about Mercury! Mariner 10 was just an appetizer... it began to show us what we don't know. Now it's time to find some of those answers. The 3 MESSENGER flybys have already given us breathtaking new images of the planet, far more detailed, and far more lovely, than anything sent back by Mariner 10. And there is much more to come.

We can hardly expect that the general public is going to get revved up about every peculiarity of Mercury. Mariner 10's results were a surprise, so now NASA hopes to answer key questions about the nature of Mercury's enormous, iron-rich core, its surface features, its magnetic field, and volatiles at the poles which may turn out to be water ice. But that may not be something you're going to go nuts about. What's important about planetary science is not always the little details that are revealed, but what those little details tell us about the bigger picture. When we are surprised in science, it means whatever model we have constructed is somehow incomplete or imperfect, so we go back and revise it. Sometimes they are little changes, but sometimes there are major implications for the field. In our search for exoplanets, for instance, we have learned that the structure of our Solar System -- terrestrials close in, gas giants farther out, with orbits more or less circular -- can hardly be considered typical, or the way it has to be. Rather, we have discovered gas giants with highly elliptical orbits, and enormous planets orbiting extremely close to their parent stars. So we have to revise our notion of how star systems may form. Similarly, the results from Mariner 10 and now MESSENGER reveal some gaps in our understanding of Mercury's formation, so we have to re-examine our assumptions.

Does the public care about that? Well, I think so. In spite of America's alleged apathy towards space science, there remains great enthusiasm for the latest discoveries. Though it seems clear that a large portion of the population is often in the dark about many of the latest astonishing breakthroughs, news of the most exciting discoveries tends to reverberate in all corners. It's rare that I meet someone wholly disinterested in the mechanics of the universe. In this case, the more we can learn about the formation of our solar system, the more we might come to understand how other star systems form, and that could perhaps give us some insight into where other life might exist, and what that life might be like. That alone is an awesome prospect, and it has profound implications for our understanding of who we are as a species, and as a planet. But we might also gain new insight into the nature of our Sun's formation, or the formation of the solar nebula, and that, in turn, could perhaps give us some clues as to what was going on in our region of the galaxy 4.5 billion years ago. As we connect these dots back in time, we are tracing our origins back, incrementally, to the beginning of the Universe. The MESSENGER mission will of course not be able to answer all of these questions, but it could help to answer some. And for 0.02% of your tax dollar, that's not bad.

The science begins April 4th. I can't wait.

Examining Alternative Theories

2011-03-04T16:48:00.021-05:00

The last several years have seen a shift in opposition to mainstream climate change theory. For a long time, global warming was regarded by the skeptics as just a hoax... in the words of Senator Jim Inhofe back in 2003, "the greatest hoax ever perpetrated on the American people." The skeptics said there was no evidence that the Earth was warming, that scientists were simply fear-mongering for the sake of fundraising, and sometimes they pointed to local phenomena, like frigid winter temperatures and brutal snowstorms, to back up their claims. To be sure, this school of thought remains a major force in the anti-science community; Sean Hannity seems to have a particular affinity for using winter storms as evidence global warming isn't happening. But increasingly there has been another argument advanced by the right -- that is, global warming is happening, but we humans are not causing it. Instead, they say, there is any number of other factors causing global warming, and as such, we need not worry about it.

There are a variety of alternative theories put forth by the skeptics in this camp. Sunspots and sun cycles have been blamed for global warming, as have volcanic eruptions, cosmic rays, and various other astronomical causes (variations in Earth's axial tilt, the fluctuating eccentricity of Earth's orbit and the precession of equinoxes as relates to perihelion and aphelion, for instance). Now, there is no question that these various factors do affect Earth's climate, and that can be seen clearly in the record of ancient climates. We know that the Earth has seen periods of natural warming and cooling, and there is no doubt that these sorts of changes will happen again. Nevertheless, these variables cannot explain the warming trend over the last 100 years or so nearly as well as anthropogenic factors, like the emission of enormous levels of carbon dioxide corresponding to the industrial revolution.

Skeptics of mainstream climate change theory may take to these other hypotheses in part because there is a sense that we humans are not capable of making big changes in our ecosystem. Of course, history tells us otherwise. Human beings have driven many species to extinction or to the brink of extinction by over-hunting and habitat destruction, and in the 20th century, with the advent of chlorofluorocarbons (CFCs), we put an enormous hole in our ozone layer. Meanwhile, we continue to possess the power to cause a global nuclear winter.

To understand how humans are capable of making such profound changes to the climate, we have to understand the two main elements behind our increased impact on the environment: the industrial revolution and recent population expansion.
Beginning in the 1700s and increasing throughout the next few hundred years, the industrial revolution was responsible for an unprecedented level of fossil fuel burning and deforestation. The natural carbon cycle of the Earth, whereby carbon dioxide is emitted by natural processes like respiration and absorbed by natural processes like photosynthesis, was upset for the first time by the artificial emission of CO2. There is no natural process on the Earth that is capable of taking the carbon trapped deep below the surface and spewing it into the atmosphere at the rate of human capacity. Second, coinciding with the industrial revolution was the staggering growth of the human population. Since 1800, it is estimated that the human population has grown from about 1 billion people to almost 7 billion people. For almost the entire history of humanity the population was under 1 billion, but just in the last two hundred years we have increased our numbers 600%. That's a lot of people, and each one of us is responsible for contributing a small portion of the world's CO2 output, natural and artificial. But just think of how many cars, trucks, trains, planes, ships and power plants there are involved with sustaining such an enormous population, and think of how much exhaust these machines dump into the air in a single year.

But of course, we're not just dealing with the carbon emissions of a single year. As the balance of CO2 emission and absorption is upset, more carbon dioxide is retained in the atmosphere, and over time this builds up. It's a bit like an overwhelmed bilge pump on a ship. Even if the pump continues to function at full power, the ship will eventually sink if the water comes in faster than it can be removed. Similarly, we are dealing with all of the excess CO2 built up since the beginning of the imbalance, so we're really facing the combined force of many years' worth of excess carbon. There is some uncertainty as to how long the carbon dioxide will remain in the atmosphere, but there is no question that the system is saturated. And by the way, we haven't stopped the activities that are causing the problem.

We know how greenhouses work. We have put them to use growing tropical plants in the winter months. But of course, our atmosphere is not made of glass, but of various gases. Carbon dioxide is one constituent of the atmosphere, and it is considered a greenhouse gas. A little bit is a good thing: the greenhouse effect is responsible for keeping the Earth warm, by trapping some of the Sun's radiation in our atmosphere. But if we are to increase the level of greenhouse gases in the air, more heat is trapped. This is just basic chemistry and physics. There can be no doubt that the greenhouse effect is responsible for keeping the Sun's heat inside, and there should be no doubt that altering the chemistry of our atmosphere will alter the behavior of the system.

What is so mystifying about the alternative global warming theories is that they are comparatively far-fetched. Just think about it. Is it more likely that the well-documented increase in global temperatures is related to the well-documented increase in greenhouse gases in the atmosphere, which correlates well to the increase in fossil fuel burning and human population growth? Or is it more likely that a number of other factors, which have historically caused changes to the Earth's climate on the scale of thousands of years, have suddenly cropped up inconveniently to raise global temperatures at a drastic rate? It is not enough simply to say that the Earth has experienced natural climate changes before, and therefore the changes we're seeing now are natural. Climate change doesn't just happen on its own, there must be some kind of forcing, and while the correlation between CO2 and temperature increase is clear, the data on other proposed factors (solar activity and cosmic rays, for example) shows no such correlation. The choice is between a theory that hinges on a straightforward mechanism with straightforward results, and a theory that relies on coincidences, uncertainty, and unpredicted phenomena. Tellingly, there is no consistent hypothesis among the climate change skeptics. A brief search on the internet will yield an abundance of alternative explanations, but there is a reason no single idea is embraced by all the opponents of the mainstream theory: none of the rebuttals are iron-clad, and most try to isolate one aspect of the evidence for global warming and tear it apart, utterly ignoring the fact that there are several independent lines of evidence that corroborate each other in support of anthropogenic climate change.

But this begs a larger question: why have opponents of mainstream climate change theory been so desperate to latch on to alternative theories? What is it about the carbon emissions hypothesis that they find so unacceptable? Is their opposition strictly based on its economic implications? Considering the issue's partisan divide, it's difficult not to conclude that the politicians on the right have criticized mainstream climate science, not so much because of flawed evidence, but because of the problems it causes for their corporate contributors. Combine this with a powerful public relations campaign on the part of oil companies, and fears in the Rust Belt of a collapse in coal demand, and we can start to understand how the truth can be obscured. There is much interest in maintaining the status quo.

We may feel sympathetic for those working class folks whose jobs are threatened by the transition to a clean energy economy. But if that is the case, we as a nation should invest in jump-starting the transition process, and making sure these hardworking Americans are trained to work in the new energy sector. No one wants to deprive these people of a job, and it's certainly not their fault that we need to give up our dependence on fossil fuels. But we also cannot continue to destroy the planet because there are jobs at stake. It will be up to the politicians to help ease the transition. And as for the overall economic impact of a clean energy revolution, it should be a net positive. The sooner we embrace reality, the sooner we can get working on making sure the United States is on the cutting edge of low-cost, high-efficiency products. As the world makes the transition to clean, renewable energy, they'll need the technology, and we should be ready to sell it.

To be clear, the Earth itself is not in great danger. The Earth is resilient, and it has seen substantial changes to its climate over the ages. We are not yet close to effecting such change. But if the rate of warming in our time is very fast, other species may not be able to adapt. Some kinds of life will survive these changes, but we may be responsible for the end of many hereditary lines in the biological world. Even so, new species will take their place. Life goes on. But we are also threatening the climate to which we humans are accustomed, and we are flirting with a global catastrophe with severe consequences for the future of humanity. Considering how much difficulty we have with sporadic flooding, droughts, powerful hurricanes, and mass population displacements, it's apparent that we are nowhere near ready to deal with these events on a larger scale. We must think seriously about our preparedness for such an eventuality, and we should ponder the tragedy of premature extinction.

It should be noted that skepticism is a very important part of the scientific endeavor. Skepticism has liberated us from mystical explanations for natural phenomena, and it helps us avoid taking assertions at face value. It is essential the we interrogate the world around us with an open mind, and it does us no good to swallow climate science, or any other science, as fact, without investigating it more deeply. It is crucial that any finding be tested and confirmed by other scientists. But that has already occurred. Global warming has been predicted and tested by science for more than 100 years. It is true that some of the most important scientific findings of ages past have challenged the conventional wisdom; the controversial heliocentric model of the universe advanced by Nicolaus Copernicus comes to mind. But not every scientific finding is erroneous, and not every fringe scientist is Copernicus. We must always be open to having our minds changed, but extraordinary claims require extraordinary evidence.

Who Can You Trust on Climate Change?

2011-02-23T16:01:00.023-05:00

Today's New York Times examines Virginia attorney general Ken Cuccinelli's one-man crusade against climate science. Take a look at it here.

The ongoing battle over climate change highlights a central problem in a population that is under-educated in science. The question is, who can you trust? For those who have not gone to the trouble of educating themselves on climate science, you just have to trust what you're being told. But for a subject as contentious as climate change, you're being told two radically different things. One the one hand, you have a large majority of scientists, who have reached a consensus. They tell us that climate change is real, and that human activity is the primary agent of global warming. Some of the details remain to be nailed down (for instance, how fast is it happening, how extensive will the damage be, how high will seas rise, etc), but the main storyline is clear. On the other hand, you have some politicians, media personalities, and a small minority of scientists, who cast doubt on the whole affair. This group can be broken up into two main varieties: those who don't believe climate change is happening, and those who do believe it is happening but think we humans are not responsible for its creation or its resolution.

The population is left to decide who is right. Who do you choose?
Since many of us identify with a political party, we sometimes have the luxury of going along with the party line even when we don't fully grasp or care much about every single issue in that party's platform. In other words, you may not know anything about climate science, but if you identify as a Democrat, you'll probably go along with the Democrats, and vice versa. But this is a troubling state of affairs, because it means that public opinion is largely under the influence of politicians, who may be misinformed or guided by ulterior motives.

When it comes to educating ourselves, we must be careful not to conflate partisan and scientific literature. Let's take Ken Cuccinelli, for instance. In the aforementioned article, he admits that he didn't know much about climate science until recently when he did "basic reading" on the subject and, in the wake of the fake scandal known as "Climategate," decided that these climate scientists were up to no good. Well, this is a problem. It's unclear what exactly he read, since most non-partisan and scientific periodicals accept climate change as established science. But if his "basic reading" on the subject consisted of articles from Andrew Breitbart and The Drudge Report -- champions of the now-debunked Climategate controversy -- he's not really getting all the facts. He's getting a partisan slant. Not all reading is created equal.

But who's actually reading the scientific literature? The academic papers are really just for scientists. The general population doesn't really know what's an acceptable level of carbon dioxide in the atmosphere. Is 390 parts per million a lot? It doesn't sound like it, but who knows? And what constitutes a big increase? A few parts per million? It's hard to imagine such small quantities having such a profound impact on global temperatures (but of course, this is a misleading number. There is really a huge amount of carbon dioxide dumped into the atmosphere every year: the United States alone is responsible for adding about 6 billion metric tons of CO2 each year). And then we get into all sorts of other complicated science problems: how exactly can we determine the global temperature of past epochs from a column of ice? How do sunspots affect global climate? How much do seismological events contribute to the level of greenhouse gases in the atmosphere? These are the subjects of much research, but this work rarely reaches the public in raw form. Instead, it is left to journalists to interpret the findings and spell it out in plain English for the rest of us.

Anyway, the problem remains: since most people are not going to be climatologists, we just have to leave it to the climate scientists to figure it out. This may sound unsatisfying, but every field of science operates the same way. Few of us have done the math to calculate the expansion of the Universe. Few of us have looked at the spectrum of Neptune's atmosphere to determine its composition. Few of us have studied quantum mechanics. Most of us are not geneticists, or computer scientists, or chemists. Consequently, we just have to trust that the Universe is expanding, that Neptune is made mostly of hydrogen and helium with a bit of methane, that atoms are made up of all kinds of exotic particles that exhibit incredible behaviors. We have to trust that there is such a thing called DNA, that microchips are the driving force behind millions of unseen processes, that water is two atoms of hydrogen and one atom of oxygen stuck together. It's easy to trust these scientists, though, because these questions are basically uncontroversial. We trust they are not manipulating their data. But it's a whole different ballgame when the scientists say something we don't like.

People in the anti-science community often accuse scientists of treating their work like a kind of religion. It's a particularly effective tactic: as much as scientists rail against dogmatic religion, they say, they seem to be equally dogmatic about science. To them, scientists are saying, "you have to believe it all, without questioning it." It's important that scientists draw a distinction here. The reality is, debate is encouraged in science, not stifled. Debate is essential for progress. But a dissenting opinion has to be backed up by a compelling alternative theory if it is to be given much credence, and this is where the opponents of science typically fall short. Whether we're talking about climate science or evolution (the other most popular subject for science skeptics), simply finding little gaps in the data is not enough to disprove the theory. You need to advance another theory that is equally or better supported by the facts, and this theory cannot be based on ideological or theological feelings.

Manipulating data to reach a predetermined conclusion is just bad science, and it should never be tolerated. But climate change skeptics have accused scientists of doing just that, on an enormous scale. The accusation calls into question the ethics of literally thousands of scientists. According to the skeptics, there is a worldwide conspiracy to falsify data, but the evidence for this is dreadfully thin. Scientists have little to gain by participating in such a massive fraud. It may be that some scientists with opposing views are afraid to speak out, but this alone is not proof of a conspiracy. The truth is, we would all love for global warming to be a figment of our imaginations, but the numbers are unmoved.

Perhaps the skeptics think the scientists are simply making up facts. This is easy enough to imagine; if we don't understand how conclusions are derived, we're tempted to think it was all just cooked up out of thin air. But just because you haven't heard about all the evidence, doesn't mean it's not there. Innumerable scientists have devoted their lives to investigating the world around us, and sometimes the correct conclusions are drawn from arcane observations. The correct conclusions can also be counter-intuitive. Strange effects are predicted and have been observed at relativistic speeds, but you need exquisitely precise time keeping to detect it. Variations of the double-slit experiment demonstrate a bizarre, paradoxical behavior of light, but you need a sophisticated apparatus to investigate it. We may not be able to fully grasp the nature of these phenomena, but they really happen. Similarly, in our day-to-day lives, we cannot experience climate change. The changes are too small, and our perspective is too local. But the data tells the story.

Education is the key. The only way to be sure who is right is to study the facts and draw your own conclusions. But if you're not able to do that, you'd be well advised to follow the scientists. There are dissenting voices, but the consensus is clear. We've got a real problem on our hands, and we've got to figure it out soon.

Why Should We Go to Space?

2011-02-04T16:24:00.022-05:00

Sometimes I ask myself, "why should we go to space?" It's a question I think many of us have probably asked ourselves. I can tell you all sorts of reasons why our exploits in space are extraordinary, but that doesn't really answer the question. It's a question that needs to be answered, though, and any advocate of space exploration should have an adequate response.

Every year, as the United States has to draw up its budget, there are lots of considerations. How much do we spend on defense? How much can we afford to take care of the poor, the elderly, the children? How much do we send abroad for humanitarian purposes? And how much do we invest in education, and technological advancements here at home? Each of these are very important, but when money is tight, we have to make some difficult decisions. We have to get our priorities in order, and the composition of the government determines those priorities, sometimes but not always along party lines.

When it comes to making cuts, space exploration sometimes finds itself on shaky ground. It can feel like a luxury item, like that cable sports package we like but don't really need. Looking at the billions of dollars spent on manned space flight or space telescopes, for instance, it's easy to wonder how many children that might feed, or how many teachers that could pay (but of course, it's an equally valid question to ask how many fighter jets and warheads we could stand to do without). No expenditure exists in a vacuum, though, so while we can easily imagine all the good that an extra 10 billion dollars might do for any single program, we have lots of commitments and we have to figure out how to spread the money around to cover all our bases.

Our ventures in space began with a decidedly defensive purpose. When the Soviet Union launched Sputnik in 1957, it became clear that we were vulnerable to an unprecedented threat: intercontinental ballistic missiles. As was typical of the Cold War, we set about the task of demonstrating our technological prowess. It was a matter of national security, after all; the best way to deter the Russians from destroying us with ICBMs was to make sure everyone knew we could do the same thing to them. But as a lovely side effect of that scary time, the United States began a preliminary reconnaissance of the solar system. In a breathtaking achievement, the US landed a man on the Moon just 12 years after the first satellite was launched, and only 66 years after the Wright Brothers' first powered flight. Since the beginning of the space age, we Earthlings have sent robotic emissaries to all of the major planets; investigated the myriad moons of the outer solar system; landed robotic spacecraft on Mars, Venus, and Saturn's moon Titan, with a few rovers exploring the Martian landscape; built an enormous space station in Earth orbit; connected the world through a dazzling array of communications satellites; and stared into the vast depths of space, peering 13 billion years into our remote past, and accumulating data that is impossible to collect from Earth's surface.

We are so incredibly fortunate to live in this age of great discovery. The human species has spent its entire modern existence -- many thousands of years -- looking up at the stars and wondering what they are. But it's only in the last 2 or 3 percent of that history that we have been able to work out some of the answers.
Our ancestors of antiquity cataloged the skies, investigating the structure and mechanics of the universe as it was then known, studying the motions of the planets and drawing some remarkable conclusions. In just the last 500 years or so, we have made the most astonishing breakthroughs in our understanding of the cosmos: discovering at last the heliocentric structure of the solar system, the elliptical orbits of the planets, the nature of gravity, the existence of new planets, the galaxies, the extraordinary properties of light, the theory of relativity, and the Big Bang. All of these spectacular discoveries were made by humans before we ever had a chance to go up in the sky and take a closer look.

This is our heritage. The thousands of generations before us lived and died with only a vague understanding of the immeasurable universe beyond our atmosphere, but their collective contributions have brought us to this pivotal moment. It's up to us now to make our contribution. If we do not, the next generation will have to do it for us, but we owe it to them to go as far as we can, so that they can go even farther.

As inspiring as astronomy can be, though, it will always be tempered by terrestrial concerns. But for the practical mind, there are tangible reasons why we must continue our work in space. We know that the universe is not static. It is a dynamic, perilous and indifferent place, and our survival depends on how well we understand our cosmic neighborhood. Earth is the only planet so far as we know where we humans can reside comfortably, but there is no guarantee that our home world will always be perfectly hospitable, and we do not yet possess the technology to escape in the event of catastrophe. It's not very likely that we'll see something like it in our lifetimes, but there is always the chance that a yet-undiscovered asteroid or comet could slam into us and end humanity's brief reign on the Earth. For the first time, we have the capacity to avoid such a calamity, but we should take appropriate steps now. Meanwhile, we know that our mighty Sun is capable of doing tremendous damage to our technological infrastructure, so it's worth continued study. Global climate change remains a serious threat, and satellites have provided us an abundance of meteorological data. At the same time, our investigations of the Martian and Venusian climates have provided real examples of what Earth might look like with a runaway greenhouse effect, or without an ozone layer.

But history tells us something else about the value of science. In many instances, scientific discoveries have had applications far beyond the imaginations of the people living at the time. When magnetism was first investigated in Ancient Greece, the navigational compass was still 1500 years in the future, and certainly no one could have imagined something like magnetic tape, which was critical to audio, video, and data recording for most of the 20th century. The importance of genetics and its promise for medicine could not have been fully grasped at the time Gregor Mendel was working with his peas. When Benjamin Franklin performed his famous kite experiment, it's unlikely that anyone could have predicted something like the television or the internet. And the pioneers of chemistry in the early 1800s could not possibly have suspected the awesome power contained within the atom.

When we look at the countless discoveries of the last few thousand years, time and time again we see a pattern of marvelous and unexpected scientific breakthroughs which could not have been possible without the work of those who came before. And such is the case today. Sometimes we just don't know what we'll find around the next corner, and we can't possibly know what that discovery will mean for the future. Scientific studies can sometimes appear to have little application for everyday society, but it's impossible to know when the next unexpected, world-changing discovery might come. We just have to keep working.

In any case, it would be a mistake to minimize space exploration's visceral appeal. There remains great enthusiasm for the latest scientific discoveries, whether we're talking about finding new exoplanets or a tantalizing astrobiological discovery. The general public is enamored with the future, and science is the means to get there. But more than that, exploration is a part of us. We have always been explorers, and when the Earth was finally mapped in its entirety, we craved a new mission. The next frontier is space, and it holds enough mystery to occupy thousands of generations to come. So far, space exploration is too expensive for most private interests, so it's up to the government to do it. But in time we can expect more private involvement in space. We are seeing the start of it now.

Space travel is the crowning achievement of human technology. Just as funding for the arts can be difficult to justify in concrete terms, it can be hard to quantify the value of our work in space. We cannot put a price tag on the expansion of human knowledge. But our space endeavors represent the pinnacle of human potential. At long last, we are spacefarers. It is our future, and we would be well advised to embrace it.

Ophiuchus! What now?

2011-01-14T18:34:00.005-05:00

I woke up yesterday thinking I was an Aries, and went to bed thinking I was a Pisces. Oh brother. I guess it means that I'm "compassionate, gentle, artistic, mystical and highly intuitive." All this time I thought I was "optimistic, independent, impulsive, playful, competitive, courageous, sometimes combative and always adventurous." Gee, I'm sort of all those things sometimes.

I really couldn't care less, you understand, but the big news yesterday in the twitterverse and elsewhere was the addition of a 13th sign to the zodiac, called Ophiuchus. Of course, it's not really a new addition to the zodiac... The constellation of Ophiuchus has always been there along the ecliptic, we've just traditionally left it off the list of the big 12 astrological signs. But it was widely reported that not only is Ophiuchus a new sign that we'll all have to learn to live with, but that the precession of the Earth's axial rotation has, over a few millennia, shifted our view of the sky so that the Sun is no longer in the same apparent position along the zodiac as it was thousands of years ago, when this version of astrology was concocted. In other words, people with birthdays in late March have traditionally been considered Aries, but today the Sun is really in Pisces at that time of year.

This story is just so silly in a variety of ways. For one thing, it wasn't actually news. The Earth's axial precession doesn't happen overnight, and astronomers haven't just discovered it (read this discussion of the problem by Phil Plait way back in 2008).. In the words of Sam Cooke, it's been a long time coming. Then there was the panic and irritation that the traditional signs are all wrong (today HuffingtonPost cleverly examined the Earth-shattering consequences of this shift). If you've got a tattoo of your astrological sign, tough luck buddy. And then there was the inevitable backlash from those unlucky souls born in late November and early December, suddenly thrust into a brand new personality profile. How would you feel to grow up thinking you're a Scorpio, and suddenly find out you're really an Ophiuchus? The name sounds like a disease. What's my birth stone? And how am I supposed to know what kind of person I am? No one has published my new attributes yet.

Then today, the astrologers came to the rescue. Nothing to fear, they said. The Ophiuchus shift only applies to Sidereal Astrology, not Tropical Astrology. Most believers probably don't know the difference, but don't worry, we westerners typically believe in Tropical Astrology, which is unaffected. On twitter I saw several people commenting in a similar, but tellingly inconsistent vein: "Ophiuchus only affects those who were born 2009 onwards. If you're born before 2009, the sign stays the same." That's a relief.

It remains to be seen whether the new dates for the 12-sign zodiac will be adopted, whether we'll keep the dates as we have come to know them, or whether we'll switch over to the new 13-sign zodiac. In other times, the astrologers might have ignored this story, let everyone just forget about it. But if this story reached a critical mass of attention, they might have a real problem on their hands. You see, this little incident has highlighted just how pointless the whole thing is. Since it has taken so long for the Sun's apparent position in the sky to change, reassurances that Ophiuchus only matters for people born now aren't very convincing. That there are two schools of thought when it comes to astrology is also a troubling revelation. If you're a casual horoscope reader, you probably have little reason to think Tropical Astrology is any more valid that Sidereal Astrology. But you'll probably just go along with whatever is easiest, or whatever your newspaper decides to use. You'd like to stay an Aries, and one of these astrologies lets you stay that way. Good enough.

But if we can just arbitrarily decide how we wish to interpret the position of the Sun and the planets along the zodiac, if we can decide that it doesn't really matter that the Sun is not really in the place astrology pretends it is, then did it really mean anything in the first place? What is the point of reading signs in the sky if we get to ignore the signs? The ease with which we can ignore these little problems, like the precession of equinoxes, is indicative of astrology's fallacy. It's easy to make things up as you go along when that's what your entire business has always been about.

Skeptics get a bad wrap sometimes. People think skeptics are just out to spoil all the fun, but that's not really what it's about. It can be fun to pretend that we are somehow tied to the motions of the planets, that there is something concrete yet ethereal steering our lives. I still enjoy fortune cookies. Maybe astrology is just a harmless pastime, but maybe not. For people who can enjoy it the way most of us enjoy a magic show -- suspending our disbelief to be amused for a few moments -- that's fine. But if anyone out there is making decisions based on horoscopes, that's a problem. If we go into it not knowing on some level that it's just an illusion, not thinking critically about what we're being told, we become susceptible to fraud and deception. But more troubling than that, this way of thinking extends beyond astrology. If we can't think critically about astrology, how can we expect to accurately evaluate the intentions of our politicians, or our clergy? We've got to ask skeptical questions if we're not to be bamboozled by charismatic charlatans.

The thing is, there are many questions with which science must continue to grapple, but astrology is not one of them. Astrology is inconsistent, and falsifiable. Just enjoy responsibly, and don't throw your money away.

Thoughts After a Tragedy

2011-01-11T12:17:00.011-05:00

Take a look at this great new video, narrated by Carl Sagan:

In the wake of horrific tragedies like the shooting in Tuscon this past weekend, we are reminded that human beings are sometimes capable of terrible things. But the events of the weekend also show that for one act of brutality, there are several acts of heroism. Such is, I believe, the nature of humanity. For all our shortcomings, and the violence that perpetuates around the globe, we remain a hopeful and curious species. Our intentions are heroic, and we long for peace. We are not born with hatred in our hearts. Our brains retain the vestiges of more violent epochs, but we have the capacity to temper our reptilian impulses of aggression, and triumph over all adversity. We have evolved for cooperation.

One of my favorites lines from Contact sums it up well:

"You're an interesting species, an interesting mix. You're capable of such beautiful dreams, and such horrible nightmares. You feel so lost, so cut off, so alone. Only you're not. See, in all our searching, the only thing we've found that makes the emptiness bearable... is each other."

It is too early to know the true motive of the shooter. It may turn out that his mental instability is chiefly to blame, that a toxic political discourse is only peripheral, and that there was little that could have been done to prevent his rampage. Maybe he's just insane. But every mass murderer could be considered insane compared with "normal" human beings. Some atrocities, like this one, may be driven by incoherent beliefs, but many others are perpetrated in pursuit of very common political objectives. Whether we are talking about suicide bombs or genocide, these actions have been carried out with at least tacit approval from a larger group of people. The line between "normal" and "insane" is sometimes blurry.

But we humans have it within us to conquer hatred. It is possible to knock down the barriers that stand to divide us. We can do it, and we must do it. We have traveled a long way to get here, and we have a long way to go. We'll have to work together. The world is just too wonderful.

The First Interstellar Missions

2011-01-10T15:39:00.022-05:00

Check out this excellent paper from Marc G. Millis, arguing that interstellar space travel could be possible in as little as 200 years. The paper calculates the amount of energy required for two types of interstellar missions, and uses estimates of world energy output growth to determine when the required energy might be available to such missions. Millis bases his calculations on the fraction of energy made available to current space missions, accounting for various technological innovations and broader considerations that might accelerate or delay serious consideration of interstellar missions. The math suggests that an interstellar spacecraft colony could be achievable in approximately 200 years, and a probe to Alpha Centauri could be launched within 500 years.

Millis' estimate is both exciting and disappointing. Space enthusiasts want desperately to see an interstellar mission in our lifetime, but of course most of us realize that's probably not in the cards. At the same time, some scientists have said it may be a thousand years or more before we are capable of interstellar space travel (that is, fast interstellar space travel), so a few hundred years is actually good news. The world is likely to be a far different place in a thousand years, but 200 years is only 10 generations or so. The English we speak today will probably remain intelligible to those lucky people in 2211. We are just barely missing the wonders that may be in store for the future, just as the great scientists of the 18th and 19th centuries barely missed the extraordinary breakthroughs that would come in the 20th century. They laid the groundwork for our world, though, and now it is up to us to lay the groundwork for tomorrow.

But where are we going, and why? Will we be diversifying our interests, spreading the seed of humanity beyond the solar system? Or are we simply going to investigate our nearest stellar neighbor and radio back the results?
Millis explores both of these options -- an interstellar probe bound for Alpha Centauri, and a 500-passenger colony ship, destination unknown, with a mission only to take a piece of humanity far beyond the domain of our Sun. It is here that Millis approaches the practical considerations, but doesn't quite explore the implications fully (though, to be fair, it is really beyond the scope of his paper... his purpose is to speculate on when interstellar travel could be possible, not to predict when it will actually be achieved). In a few hundred years, we can expect the capabilities of our space telescopes to have expanded considerably, so a mere flyby or rendezvous with the Alpha Centauri system may tell us little; it would be of great academic interest to send a probe there, but what will we learn that we could not learn from observations with our telescopes? Of course, that is the great question! But if there are any planets to be found there, we should be able to detect them long before such a mission is possible. It remains to be seen, but the existence of planets in the Alpha Centauri system would immediately make this mission more appealing.

If we are considering the colony ship for the purpose of placing our eggs in other baskets, a whole mess of other questions come to mind. Why not simply send our colonists to other planets or moons in our own solar system? Well, we may have already done that. Interestingly, though, Millis' calculations indicate that the colony ship will actually be feasible long before the interstellar probe to Alpha Centauri, about 260 years earlier. This is based on the required delta-v for the probe to rendezvous with Alpha Centauri, and the requirement to reach a speed consistent with tolerable limits on mission duration (Millis selects 75 years). But what good does it do setting 500 people on a course to nowhere? What do they do if they need to slow down, or land somewhere? (There is no built-in delta-v to slow down this craft in Millis' calculation). Will we really be able to build a spacecraft large enough to carry 500 people, indefinitely, in the next 200 years? Again, these questions are beyond the scope of Millis' paper, but they are relevant to the question of when we will achieve human interstellar travel. A self-sustaining human colony floating endlessly in space, set adrift from the rest of humanity, is a somewhat unappealing notion, and besides, we can hardly assume a spacecraft launched in 2211 will be able to house human beings safely for centuries or longer in the vast depths of space. There are bound to be minor malfunctions, electronic failures, and occasional hull damage, but spare parts will be hard to come by. And eventually, one would think that they'd want to settle on another world.

With these considerations, and taking into account the anemic funding afforded space travel these days, it's easy to see that Millis' estimates for achieving these goals, while perfectly reasonable, may represent an exceedingly optimistic time frame. In other words, Millis has shown us what is possible, but it's far from assured that we will meet the mark. We will need to see some remarkable advances in propulsion technology if the interstellar probe is to be realistic anytime soon, and though the energy may be available to launch a colony ship in the next two hundred years, from a practical standpoint it is beyond the pale. In 200 years we may be sending many humans to live on Mars or elsewhere, but I doubt we will be sending any to drift in interstellar space forever. In fact, the only reason we would have to escape the Solar System, rather than simply take refuge on another planet or moon in our vicinity, would be the death of our Sun. But that's not going to happen for another 5 billion years or so.

While Millis' estimates and their implications may be disappointing, a realistic evaluation of these time scales is useful. When we fully appreciate the great distances between our solar system and others, we begin to understand just how important it is to learn about our own planetary neighborhood, where travel time is relatively short, and where we may one day set up human colonies. There are lots of places left to explore, and it is still a good idea to put our eggs in other baskets. But this ultimately brings us back to the most basic concern: our own survival on this planet. The Earth is the only place in the Universe, so far as we know, where we can live perfectly comfortably. We have been sculpted over billions of years of evolution to be perfectly tuned to our environment -- we are accustomed to the pressure, temperature and content of our atmosphere, and the nutrients of the soil are passed on to us through the food chain. Here on Earth, we have all the water we could ever need, and the Sun banishes the cold and darkness of space. It is truly a paradise. But this paradise is by no means promised to us, and today natural and man-made terrors threaten to destroy the planet, or at least extinguish the human species. Whether we are talking about nuclear war, global warming, or a cosmic collision, we must do everything in our power to avoid these calamities. We owe it to our ancestors and descendants alike. For those who dreamed of visiting the stars, and for those who may one day reach them, it's up to us to get there.

Questions for Young-Earth Creationists

2010-12-07T16:28:00.053-05:00

Last Wednesday, Kentucky Governor Steven Beshear announced that millions of dollars in taxpayer funds will be going to Ark Encounter, a planned Christian creationist attraction similar in theme to the infamous Creation Museum (also in Kentucky). Both attractions are sponsored by Answers in Genesis, a particularly zealous creationist group that adheres to a Young-Earth cosmology as part of their belief in a literal interpretation of the Bible. According to their beliefs, the Earth and the heavens are somewhere in the vicinity of 6,000 years old.

As you would imagine, this has sparked the usual debate over separation of church and state, and of course I'm inclined to agree with those who really don't want their money going towards such things. But the Governor seems to have mostly diffused the controversy on economic grounds, noting that the attraction will generate millions in tax revenue and create hundreds of jobs.

In light of this rejuvenated debate, I thought it might be a great time to present my Questions for Young-Earth Creationists, which I promised several months ago. Here goes:

1. Do you believe that the speed of light is approximately 300,000 kilometers per second? If you don't, how fast is it? And how do you know that?
The actual speed of light is 299,792,458 meters per second, we just round it off to make basic calculations easier. But we need to know exactly how fast it is for a variety of reasons. For instance, our GPS systems wouldn't work if we didn't know precisely how fast light travels, since the technology requires very exact calculations of signal transmission times to determine your position. Our understanding of light is essential to our use of radios, computers, and communications satellites (to name just a few). The speed of light was first measured in the 1600s, and by the 20th century we were able to measure it with astonishing accuracy. Meanwhile, independent evidence supporting our calculation of light speed is abundant. The communications delay with the Apollo astronauts, and our robotic interplanetary spacecraft, is consistent with our understanding of the speed of light, and we have even used it to measure the precise distance to the Moon using a laser and a mirror left on the surface in 1969.

2. If you believe in the speed of light, then, do you believe that the stars and galaxies are very far away, or are they much closer than scientists maintain?
Measuring the distances to the stars is a complicated problem, but astronomers have come up with a number of clever ways to do it. The stars have been found to be many light years away, and observations have demonstrated that our Milky Way Galaxy is about 100,000 light years in diameter. But if we are to believe in the Young-Earth cosmology, we would only be able to see a small number of nearby stars. For anything farther than 6,000 light years, there would not have been enough time in the age of the Universe for the light to reach us. We would not be able to see even a single galaxy outside of our own (the closest of which is 25,000 light years away). As it turns out, though, we can see very many galaxies. Most of them are millions or even billions of light years away.

3. If you believe the stars and galaxies are much closer, do you believe in gravity?
Let's imagine for a moment our calculations of the distances to the stars are way off, so that they are much closer than typical estimates. What are the implications? Well, the Universe would be a much more crowded place. Let's say the Milky Way galaxy is a mere 5,000 light years across, instead of 100,000 light years as we have said. Astronomers have calculated the number of stars in the Milky Way to be in the hundreds of billions. With a hypothetical Milky Way 1/20th the size, the volume is only about 0.0124% that of the original, meaning the stars would have to be a whole lot closer together. And such a crowded galaxy would certainly complicate things as the mutual gravity of the stars would be much stronger. In this model, using the current star count, stars are on average only 0.2 light years apart, so we could say that Alpha Centauri, the closest star system to the Sun at 4.37 light years away, might now only be about 1/5th of a light year away, much closer to the Sun than the theoretical Oort Cloud of Comets.* It's easy to see how such a situation would radically alter the dynamics of our otherwise peaceful solar system. But it could not be reconciled with observation. Parallax would show that Alpha Centauri is clearly not this close, and the same would go for all of the other nearby stars, so we would have to say that the stars in our immediate vicinity are far apart as we have observed, but they are incredibly bunched up everywhere else. Of course, there is no good reason why this should be the case. The observed stellar motions about the galactic center just cannot be squared with this cosmology. Our current star count would have to be wildly inaccurate, or our measurement of stellar masses would have to be way off. But based on what we know about stellar mechanics, we cannot just reduce the masses of the stars without noticeable consequences, so this doesn't explain it. Otherwise, we would have to be living in an incredibly dense little galaxy. But this just does not match observations. In addition, this sort of hypothesis cannot come close to accounting for the enormous number of galaxies we have observed, which would all have to be within our 6,000 year light horizon if we are to see them. If everything we see beyond the Milky Way is within 6,000 light years, the galaxies would have to be incredibly small (much too small to be considered galaxies), dangerously close together, and their measured redshift could not be explained.++

4. Do you believe in radioactive decay? If not, why not?
One key way scientists have been able to determine the age of the Earth is through the use of radiometric dating. Remarkably, every elemental isotope has a predictable rate of radioactive decay, which means we can look at any material and determine its age based on the decay of its constituent nuclides. Using this method, scientists have found the oldest rocks on Earth to be over 4 billion years old. Radiometric dating has also been used on rocks from the Moon, and meteorites recovered on Earth, and the results have consistently pointed to a Solar System in the vicinity of 4.5 billion years old. Studies of orbital mechanics and the evolution of our Sun also corroborate this estimate. Meanwhile, our understanding of radioactivity is central to modern chemistry and critical to the production of nuclear weapons and nuclear energy, so it's unlikely that we would be able to pull off such complex feats without a clear sense of radioactivity's basic mechanism.

5. In short, do you believe in science?

After just a brief exploration of some of the problems with a Young-Earth cosmology, it's easy to see just how many backflips are required to square such assertions with the facts. In order to prove a Young-Earth hypothesis, we couldn't just disprove one of the aforementioned scientific findings; we'd really have to disprove them all. And unfortunately for the creationists, this is really a tall order (you'll notice, I haven't even addressed perhaps the most elegant evidence of Earth's ancient history -- evolution -- which they dismiss out of hand). What science deniers don't seem to understand is that every single assertion in science has to be tested if it is to be counted as fact. We didn't simply take Newton's word on it that gravity works the way he said it does. It was tested, and it has been demonstrated to be correct. The same is true of Einstein's mind-boggling prediction that time dilates at relativistic speeds: it's been demonstrated. And down the line we go... every minor scientific detail, down to the most esoteric and obscure, has been worked out -- proposed, tested, and critiqued. And there is extra scrutiny reserved for the explanations of phenomena that we cannot actually see with our own eyes, whether we're talking about quantum mechanics, astronomy, cosmology or geology. Creationists like to insinuate that scientists are just making up their facts as they go along, but that accusation really betrays them; they are the ones with the unsubstantiated claims, and they are clearly unaware of the rigor with which ideas must be tested before they become mainstream theory. Scientists don't have the luxury of simply inventing their own version of history, so it has taken centuries, and the life's work of countless scientists, to reach our present understanding of the world.

In watching Richard Dawkins' fascinating interview with creationist Wendy Wright, one gets the sense that perhaps creationists may really just lack a clear notion of what "scientific evidence" means. They are apparently unconvinced by the massive amount of empirical evidence to support our modern understanding of the Universe, but they are perfectly willing to take a single text written thousands of years ago as an infallible history of the world, and manipulate their science to match a predetermined cosmology. Unfortunately, it seems clear that there is a major misinformation campaign underway, whereby legitimate science education is stifled or questioned, and a nonsensical alternative is presented as fact. The Creation Museum and now Ark Encounter are tools in this vein, and insomuch as they undermine science education and poison the minds of the next generation, they are undeserving of public funding.
-----------------------------
*Let's use this math as a jumping off point... Using a crude calculation (volume of a cylinder = Pi * r^2 * h), we estimate the volume of the real Milky Way to be about 23.6 trillion cubic light years (radius is 50,000 light years, average height is 3000 light years). Estimates place the number of stars in the Milky Way somewhere between 200 and 400 billion, so taking the average (300 billion), we divide that into the total volume and get the average volume surrounding each individual star, equaling 78.7 cubic light years. Taking the cube root, we get 4.3 light years as our average distance between the stars (remarkably close to the actual distance from our Sun to Alpha Centauri). But now we calculate the volume of our hypothetical Milky Way galaxy with a diameter of 5,000 light years and an average height of 150 light years (1/20th the size of the real thing). With these values, the volume comes out to be 2.95 x 10^9 cubic light years (0.0124% of the real thing). Dividing this by 300 billion, we get a average volume surrounding each star of only 0.0098 cubic light years, and the cube root of that is about 0.2 light years.

++ Note: This hypothetically miniature Milky Way is not part of creationist doctrine, so far as I know. I’ve just discussed it here as a thought experiment, to explore how the galaxy might have to appear to us if we are to take some ideas to their logical, if absurd, conclusions. A number of alternative theories have been put forth by Young-Earth creationists, however: They have placed the Milky Way at the center of the Universe, to explain the apparent redshift of distant galaxies; they have proposed that our section of the Universe is under the influence of a white hole, so that time has been distorted in such a way that what has been experienced as 6,000 years here on Earth has been equivalent to billions of years elsewhere in the Universe; and they have suggested that perhaps the starlight we see in the sky was actually already in motion when the Universe was created, so even phenomena we witness in our own time, like a supernova we saw last week that is estimated by astronomers to have exploded 100,000 years ago, were actually set in motion by God 6,000 years ago, and they have just been designed to seem like ancient events (this last one is a particularly troubling and altogether ironic theory, since it means that God is deliberately deceiving us here on Earth to make us think that the Universe is old, when really it’s young. What a trickster!). These theories are put together by fringe scientists, in the employ of creationist organizations, and clearly they are designed to support a particular ideological conclusion. But they are a clever bunch; by talking about white holes, redshifts, and the speed of light, their arguments sound very scientific, and to a casual or pious audience, that’s good enough.

Happy Thanksgiving!

2010-11-25T17:20:00.001-05:00

Here's wishing you and yours a very happy, safe and relaxing Thanksgiving. We are truly fortunate to live in this time, when we as a species are coming to know the wonders of the universe for the first time in the history of our planet.

Above, a special greeting from crew members aboard the ISS.

A One-Way Trip To Mars?

2010-11-17T13:30:00.018-05:00

Every now and then there is a flurry of news stories about a mission to Mars and what it might look like. A few scientists, or a former astronaut perhaps, will come out with an opinion and the debate is rejuvenated in the mainstream media for a couple of news cycles. Well, yesterday seemed like one of those times, with another suggestion that perhaps we ought to send astronauts on a one-way trip to the Red Planet, so that they could build a small colony and live out the rest of their days as the first pioneers on that barren world. (Make sure you also check out this article from New Scientist on the major obstacles that will complicate any Mars mission plans for the foreseeable future).

A one-way trip to Mars is a provocative suggestion. It's certainly an unsettling prospect, but it's also quite imaginative. And of course there is some basis in history for making such an uncertain voyage: when the first settlers of the New World crossed the Atlantic, they had no more than a dim notion of what to expect when they reached their destination, and a return to Europe was hardly assured. The vast expanses of ocean were about as immense and inhospitable to them as interplanetary space is to us today. And then as now, there was no hope of rescue in the event of a catastrophe. Still, there are some problems with this analogy -- the colonists of the 15th, 16th and 17th centuries could expect there would be fresh water, flora and fauna of some kind when they landed. Life would be rough, but they would be able to live off the land sooner or later.

Though Mars is by far the most clement world in the Solar System aside from our own, it is hardly hospitable. The atmosphere is only about 1% as thick as the Earth's, and at its warmest Mars is still very cold. Mars also lacks a magnetosphere, which means dangerous radiation from the Sun is not deflected from the surface as it is on Earth (the astronauts would also have to deal with hazardous radiation on the journey itself, though perhaps their ship will be equipped with a prototype artificial magnetosphere). And liquid water on Mars' surface is impossible.

Dirk Schulze-Makuch and Paul Davies, authors of the proposal in "To Boldly Go," argue that their plan is based around preserving the health of the astronauts and kick-starting the colonization process. But from a logistical standpoint, the appeal of sending astronauts on a one-way trip would be its comparatively low cost, as just about every objective in space is weighed against the costs. The cost of sending astronauts to land on the surface and return them to Earth is prohibitive. You'd need enough propellant to get there -- and back -- and food supplies for the several-month journey each way. In space travel, weight is money. Every little bit costs something, and quite a lot in fact. On the space shuttle it costs thousands of dollars per pound of payload. And when you consider that a gallon of water weighs about 8 pounds, you can start to understand why NASA has invented a device so that astronauts aboard the International Space Station can recycle their own urine for drinking water. But for a trip to Mars we need to get this spacecraft much farther than low-Earth orbit, so you can imagine how costs will multiply.

But maintaining the health of the astronauts is still a major hurdle. In addition to the solar radiation bombardment, astronauts on a mission to Mars will endure long periods without gravity, and their bodies will deteriorate significantly. Their bones will wither, their muscles will atrophy, and when they return to gravity their weakened hearts will pump less blood into their brains. Astronauts aboard the ISS experience these same problems, but when those astronauts come back to Earth after months in space, they have a team of physicians caring for them and they get to take it easy for a while. Our first astronauts on Mars won't be so lucky. Sure, Mars' surface gravity is only about one third of Earth's, but this still poses a serious problem. What about a spinning spacecraft to create artificial gravity, you say? Well, the physics dictate that such a spacecraft, simulating a 1g environment, would have to have a very large diameter, or it would have to spin at a rate that would be uncomfortable for its passengers. How large? Well, try some calculations on your own. Such a spacecraft would have to be assembled in space, and given our current rate of assembly on the ISS, that would take years. And then we'd have to actually launch the thing towards Mars. At this point it's an unreasonable option. So we can expect our astronauts to have a tough time setting up a base and preparing for a permanent stay.

As we have to contend with weight restrictions, one intriguing suggestion is to send the bulk of our astronauts' supplies ahead of time. Why not? There's no reason they have to carry anything other than supplies for the initial journey with them as they fly to Mars. In this scenario, a return to Earth is more feasible. Perhaps the astronauts could rendezvous with an unmanned supply ship in orbit before descending to the surface. Perhaps the ascent stage, necessary for getting off Mars again, is attached to this orbiting fuel and supply station. And either this, or another spacecraft, contains everything necessary for getting home. If we launch them early enough, we could give these unmanned craft years to reach Mars, so they could use less fuel. Perhaps they could be equipped with enormous solar sails, as that technology will hopefully come into its own over the next few decades. Though we are building two or possibly three spacecraft for this job, it's better than trying to launch one ship with everything necessary for the round trip. And only one craft need have life support systems.

In this case, then, it seems like finding a way for these astronauts to get home should be easier, and more affordable, than marooning them on Mars and committing ourselves to an indefinite stream of re-supply missions. We can't simply send them there and have them fend for themselves. Even if they are growing their own food, we can hardly expect to simply forget about them, and it's unlikely they will be able to build anything substantial on the surface without significant support from Earth. And besides, let us not forget that an off-world colony has yet to be tried anywhere yet. Perhaps we would be well advised to try a Moon base first, where astronauts could get home in a matter of days should something go wrong. A Moon base would have its own challenges, of course... 14 days of light and 14 days of dark (which complicates the use of solar power), extreme temperature fluctuations, and possible meteorite punctures. But there would be no dust storms, and it would be anywhere from 93 to 650 times closer to Earth. Among other advantages, inhabitants of a Moon base could enjoy virtually instantaneous communication with Earth. This is not to say that a Moon base should precede a mission to Mars, but that we would probably be well advised to try it before talking about a Martian colony.

As for the health of the astronauts, these problems aren't going away, and the authors of "To Boldy Go" are right to consider it seriously. But hopefully the medical advances of the next few decades will be able to solve some of these issues. We can imagine better exercise equipment and routines, improved dietary supplements and medicines, and who knows what we might be able to do with stem cells in the future. To me, these sorts of advancements are a more reasonable solution than simply avoiding the return trip to Earth. One day, hundreds or thousands of years from now, when humanity may be venturing out into interstellar space, we may well have to send astronauts on a one-way trip. But today, we have the capacity to navigate the inner Solar System with relative ease, and we should not let comparatively minor obstacles stop us from landing a man on Mars and returning him safely to the Earth.

You can see why it's a controversial subject when you get down to the details. Some people want us to get to Mars as soon as possible, while others think we need a Moon base to get ourselves in shape before making more daring journeys into the abyss. President Obama's proposal calls for a manned mission to an asteroid as a precursor to a Mars mission. This will be an extraordinary challenge in its own right, but it may prove to be an important middle step. A rendezvous with an asteroid will not be very different from a spacewalk, as the asteroid's surface gravity will be very low. The trip may take as long as a trip to Mars, but we would not need to contend with Mars' gravity when we try to come home (some scientists have suggested that a mission to one of Mars' two small moons would be a good idea for the same reason).

This much is clear, though: sooner or later we will send our first human emissaries to Mars, and that will be a voyage for the ages. But we have much to do before we take that historic step. I hope I'll be around to see it.

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The World Carl Would See

2010-11-09T15:06:00.022-05:00

"For the first time we have the power to decide the fate of our planet and ourselves. This is a time of great danger. But our species is young and curious and brave. It shows much promise."

Carl Sagan would have been 76 years old today, and boy do I wish he were still around.

The world has seen such astonishing scientific and technological breakthroughs since his death in 1996, and he would have loved to see them. With our telescopes and our spacecraft we have seen farther into the depths of space than ever before, and for the first time we are coming to know a host of new worlds orbiting neighboring suns. We have witnessed extraordinary achievements in medicine, including the isolation of embryonic stem cells and the mapping of the human genome. Meanwhile, personal computers have become powerful enough so that anyone can explore the Solar System from home. The evolution of the internet has put once-arcane scientific knowledge at the fingertips of anyone who seeks it, and it has allowed citizen scientists from all over the world to work on cutting-edge projects in astronomy. As a species, thanks to advances in telecommunications, we are interconnected as never before, and that has given rise to an awesome array of new phenomena and new challenges.

Among the many advances in the fourteen years since his passing, perhaps nothing would have thrilled Dr. Sagan as much as the search for exoplanets. A handful of planets had been discovered in the last few years of his life, but the explosion of new discoveries -- almost 500 confirmed extrasolar planets to date -- has just occurred in the last decade or so. As new technology comes online, that count is likely to expand dramatically, and we will come to find planets that are more and more Earth-like. The discovery of these small, rocky planets, and most recently the possible discovery of a potentially habitable world, gives us new hope that our galaxy may be brimming with life, that we are not as alone as we feel in the vast expanses of the Universe. We know that we may be centuries away from setting eyes on the unknown wonders beyond our Solar System, but we can dream about the future and ponder the fate of our species.

It's easy to imagine Sagan's enthusiasm for our more local projects, as well. Since his death, three stunningly successful rovers have explored the surface of Mars, and they have returned breathtaking images of its desolate landscape. The Cassini mission, likewise, has given us incredible new pictures of Saturn and its moons. As we speak, the New Horizons spacecraft is zooming away from the Sun for a 2015 rendezvous with Pluto, where it will send us the first ever close-up photographs of that frozen world. The Japanese space program has recently demonstrated the viability of the Solar Sail. And Sagan would have been delighted to know that the twin Voyager spacecraft, now in their 33rd year of operation, are still dutifully calling home from the far reaches of the Solar System, and providing us with valuable data from the edge of the heliosphere.

But these last several years have also been trying times in the country and the world, and Sagan's voice would have been a welcome one in the mix. Through the uncertainty of the Cold War, with the threat of nuclear holocaust constantly on the horizon, he was a champion of peace and reason, and through science he showed us the grandeur of the cosmos and the ultimate pettiness of our worldly squabbles. He taught a healthy skepticism for authority, and a commitment to pursuing the truth no matter where it might lead. We could use a refresher course in these areas. Today, as global temperatures continue to rise more or less unchecked, and climate scientists are under attack from conservative ideologues, we need strong advocates for science, and Sagan may have been as good as they come. In this time of religious zealotry, birthers and death panels, Sagan would have reminded us to use our Baloney Detection Kit.

In the wake of a tough election, and the ascendancy of an anti-science majority in Congress, it's easy to embrace a bleak outlook on the future. But perhaps what was most compelling about Sagan's work was his optimism. Our future is by no means assured, but we have it within us to transform the world. If we can protect the planet and confront extremism in any form, we may yet avoid self-destruction. And one day, perhaps, we may venture to the stars.

And now, another look at one of my favorite videos - Sagan's Pale Blue Dot:

Climate Change and the GOP

2010-11-02T10:54:00.014-04:00

Tomorrow, when the sideshow lunacy of campaign season begins to subside, we will face a new political reality that will dominate the next two years. By every indicator, Republicans are poised to take control of the House, and perhaps the Senate. It's possible that Republicans with their new responsibility will try to forge a partnership with the President and govern from the center. But if the last two years are any guide, we are more likely to see a new level of stagnation, a political stalemate where Congress refuses to take up any of the President's initiatives and the President vetoes everything that comes down the pipes from Congress. Sounds like a mess.

Party platforms encompass a whole range of issues -- the economy, the budget, and international relations, for instance -- on which reasonable people can disagree. But a troubling feature of the 2010 political landscape is that there is another stark dividing line between the two major parties. One side believes in science, the other does not. Consider this: every single Republican senate candidate this year doubts or denies that humans are responsible for global warming.

It wasn't long ago that moderate Republicans like John McCain and Lindsey Graham were willing to break with their party and work on climate change legislation. Of course they differed with Democrats in the way the legislation should be written, but they genuinely wanted to stop global warming. But it appears those days are over, at least for now. It's not that these moderate Republicans have changed their minds on the issue, but that they face enormous pressure from the right to conform with far right ideology. Any Republican who isn't sufficiently conservative risks a challenge from the right, and as we've seen this year, those challenges have been stunningly successful.

Meanwhile, the science on this issue is unambiguous. But remarkably, public opinion in the United States has been going in the wrong direction. A recent Rasmussen poll found that only 39% of Americans believe human activities like burning fossil fuels are chiefly to blame for climate change. More Americans believe long-term natural trends are causing global warming.
This is cause for concern, because if we think sunspots or volcanoes are the primary agents of global warming, we are unlikely to reduce energy consumption and make a serious effort to transition to clean, renewable energy. The steps we must take to mitigate global warming are not going to be easy, but they are much more difficult when we have to keep waging the public opinion war. And unfortunately, it has been politically advantageous for one side to exploit doubts over global warming and fears of the big government conspiracy to make us all drive electric cars.

I'm always intrigued when I hear people blame sunspots for global warming. While it is certainly true that sunspot activity can be a contributor to changes in Earth's climate, the science on this matter is a bit complicated and somewhat esoteric. My guess is, most people who are blaming sunspots for global warming don't know much about the actual science involved, and they're simply recycling a science-y sounding argument they've heard from skeptics on the right. But this much is certain: since the industrial revolution, and especially since our population and technological explosion of the last several decades, humans have dumped carbon dioxide into the atmosphere at an unimaginable rate (in a year, the United States adds about 6 billion metric tons of carbon dioxide to the atmosphere). Of course, carbon dioxide is invisible, but we are able to measure it. We know that carbon dioxide is a greenhouse gas, which means the more we put into the atmosphere, the more heat that is trapped. And the correlation between the increase in carbon dioxide emissions and rising global temperatures is clear.

But so long as there is a voter who is uninformed or easily swayed -- especially one who is predisposed to distrusting Democrats -- there will always be politicians who are more than happy to capitalize on global warming skepticism. They may even abandon their true beliefs in the process, but oh well, that's politics. And anyway, that makes protecting the oil companies that much easier.

Too bad for us, the future is at stake. Don't forget to vote today.

The Imperative of Asteroid Defense

2010-10-26T11:46:00.013-04:00

The aftermath of the Tunguska Event, an impact from space in central Siberia.

Check out this Op-Ed in today's New York Times from Russell Schweickart, former astronaut and co-chair of the Task Force on Planetary Defense.

Asteroid defense is a subject that doesn't get nearly enough attention. Of course we don't want to alarm people, but at the same time, maybe people need to be a little more alarmed! That may be the only way to really see some action on this front.

When you think about it, it's sort of surprising that we don't devote more energy to asteroid defense. We actively scan the skies for near-Earth objects, but in terms of actually deflecting an asteroid from a collision, our plans at this point are only theoretical. It's surprising because it seems like we should be able to get everyone on board with this mission. For some people, space exploration is seen as an esoteric endeavor, lacking practical purpose. But what could be more practical than defending the planet from a clear and present danger? To me, asteroid defense should be much easier to rationalize than studying the geology of the Moon or sending astronauts to Mars.

The problem is that this is an issue that sounds fanciful. We've all seen Armageddon. You start talking about preventing an asteroid collision and everyone thinks about Bruce Willis flying up there to blow it up, with Aerosmith providing the soundtrack.

But we all know what happened to the dinosaurs. What's so far-fetched about an asteroid collision?
Even though impacts of that size are exceedingly rare, smaller objects are much more common and can do plenty of destruction. Let us not forget the Tunguska Event, the 1908 impact of a space object in central Russia that caused an explosion estimated to be as much as 1000 times more powerful than the atomic bomb dropped on Hiroshima. That was more than 100 years ago, and it came down in such a remote corner of the Earth that few people other than space enthusiasts even know about it today. But it could just as easily have come down in New York City, in 2008 rather than 1908. As Schweickart points out, this sort of impact occurs every 200 to 300 years, statistically speaking. But that doesn't mean we have nothing to worry about. If you average two such impacts in 400 years, they don't have to be 200 years apart.

This is not the sort of project that we can put off indefinitely. A mission to Mars can be delayed five or ten years and it won't make much difference; the lives of millions don't hang in the balance. But what if we were to discover an object that's going to hit us in the next five years? Is that sufficient lead time to get the project going today? Would we have to contend with congressional skepticism? I can hear the carpers now: "Are we really going to spend 10 billion dollars on a project to protect us from this rock you say is going to hit us? We don't even know where it's going to land, do we?"

If there were more champions for this cause, I can imagine it might be similar to the fight over climate change. There would be those who would want to prepare for it, and those who would think it costs too much to prevent something that might not cause any harm in our lifetime. But think of the huge amounts of money spent on missile defense during the cold war. That danger was very real, but ultimately, thankfully, nothing came of it. The expenditures required for asteroid defense would be tiny by comparison. But unlike the prospect of nuclear war, which was possible but avoidable, the impact of a large object from space is inevitable given enough time. We just don't know when it might come. It could be 100, 200 or 300 years from now, but it could be much sooner than that. We owe it to the citizens of Earth -- even those who may not be born yet -- to start preparing for this scenario now.

President Obama's new plan for the future of NASA calls for a manned mission to an asteroid. Assuming this directive is not changed in the years to come, this will be an astonishing achievement. But even more than a manned mission to Mars, it may prove to be of vital importance to the future of life on Earth. We won't just be going to look around and take some soil samples. We'll be learning how to interact with an asteroid. And one day that knowledge could save millions of lives.

Scientists will be quick to point out that catastrophic impacts are still quite rare, and furthermore, the chances that an impact will occur near a major metropolitan area are smaller still. But we might not be able to determine the object's precise trajectory until it's too late. An object capable of destruction equivalent to Tunguska could land anywhere on Earth, killing millions, or killing no one. But a serious effort to plan for this contingency will be worth the cost no matter how many lives are at stake. There are certainly more immediate concerns on our horizon, but such will always be the case until the day we find the big one coming straight for us.

"Teach the Controversy" - The Treacherous Lingo of Crypto-Creationists

2010-10-20T16:53:00.023-04:00

The New Scientist gives us this brief update on the state of Intelligent Design in our schools today.

Creationists and proponents of Intelligent Design love to use tricky language. One of their favorites lines is, "teach the controversy," a seemingly moderate and innocuous statement that drips with anti-science subtext. The idea is to attack science on its own terms. By suggesting that there is some sort of cover-up conspiracy to teach evolution and hide its flaws, it calls into question the scientific integrity of everyone in the field who subscribes to it. Science, of course, is committed to an unbiased airing of all the facts, and letting those facts speak for themselves. And only when all the facts are available can we draw an informed conclusion.

Here's the problem: Creationism at its core is not based on facts, it's based on theology. And when it comes to science, "for the Bible tells me so" just doesn't pass muster.

Now, Charles Darwin devoted pages and pages in The Origin of Species to discussing problems with his theory of evolution by natural selection. He even conceded that some of the problems were serious threats to the whole idea. Of course, many of these problems have since been resolved, but there remain some questions (Darwin writes at length about the gaps in the fossil record, for example -- a favorite talking point for creationists today). Just because there are questions about a theory does not mean the theory is unproved, however. For instance, we still have questions about the nature of gravity. We know how it works in the everyday sense; we know how to calculate trajectories for spacecraft and planets; we know about stellar and galactic formation, including the creation of black holes; and we know how gravity can actually bend light. But we do not know exactly what happens inside a black hole, and we have yet to reconcile the gravitational force with the other known forces of the universe in a unified field theory. These are questions for the years to come. But obviously, no one is questioning the fundamental concept of gravity. That's probably because it's not considered a serious threat to the existence of God, though it's fun to imagine the wacky beliefs that might be held by non-gravitationalists.

The problem we face today is not that the creationists want the real unresolved questions of life and evolution to be discussed in class, but that they want their own scientifically unsound complaints to be given equal weight in the science classroom. Abiogenesis, the study of life's origin on Earth, is still very much an open question. The gaps in the fossil record, though there is a reasonable explanation for them, deserve to be mentioned in the science classroom, in the proper context. But irreducible complexity, another favorite talking point for creationists, has been shown to be erroneous time and time again. For the uninformed, irreducible complexity may sound like a powerful argument, but when we look at the diversity of life on Earth there is plenty of evidence to contradict it.

These science-deniers, like Republican senate candidate Christine O'Donnell, whose statements on this subject have drawn much publicity in the last several weeks, believe that evolution is a myth. In their view, presumably, evolution by natural selection was cooked up by Darwin as a thought experiment, wholly unsubstantiated by evidence. For the past 150 years, they must believe, scientists have blindly held up this single work as unassailable doctrine. They believe there is no evidence because they have not seen or read about it, or they choose to ignore it. This being the case, why should these people be dictating the material taught in science classrooms?

We return to "teach the controversy." I'm all for teaching the controversy -- in a history class, or in a US government class. Every student should learn about The Scopes Trial, and the fight over creationism in schools today is certainly worthy of discussion in social studies classes. But pseudoscience has no place in a science classroom.

In science, we cannot simply make up causes for phenomena in nature. We can hypothesize, but every hypothesis has to be tested if it is to be given any merit. Sometimes there is more than one hypothesis that, based on the facts, could adequately explain something in nature, and in those cases the question remains open, waiting for more evidence. But when we don't understand something, we cannot just give up and say a magician in the sky is responsible. Science would get nowhere if we did that. And in spite of their opposition to science, I would bet the creationists enjoy some of the comforts science has provided them. For example, I'm sure they care about what the weather will be like today, and their local meteorologist is there to help them decide whether they need to take an umbrella. But what if we thought the rain was just God crying? And thunderstorms meant God was angry? If we resigned ourselves to such thinking, we would be unlikely to decode the complexity of our atmospheric patterns. Unscientific explanations like these provide us with nothing useful, and they can stand in the way of really useful scientific discoveries.

Creationists tend to think that science is out to prove that God does not exist. While that is certainly true for some scientists, it is not what science is about at its foundation. Indeed, few of us would be dismayed to learn that the benevolent God of the New Testament really exists, and that we are all destined for paradise after we die. And few of us want to prove God doesn't exist so that we can go live hedonistic lifestyles. Science is merely a tool for understanding the knowable world. But it's a precious tool, a vital tool, and we must defend it from the corruption of transient ideology.

Update: Listen to this nonsense from Glenn Beck's radio show on October 20th:

And now, enjoy this classic Richard Dawkins showdown, in seven parts:

Sticks or Carrots? - The Way Forward on Clean Energy

2010-10-13T15:53:00.013-04:00

Check out this article from David Leonhardt at the New York Times, examining the pros and cons of Cap and Trade legislation and the benefits of increased funding for clean energy research. It's worth reading.

Cap and Trade, which at one time was the climate change compromise plan of prominent Republicans like John McCain, failed to get through Congress this year. But as Leonhardt points out, the defeat is not the end of the road for climate change mitigation. If anything, it's a chance to start again on a more popular and possibly more effective approach. Had it passed, Leonhardt says, the Cap and Trade plan might not have been as successful as had been suggested, since it does little to curb the carbon emissions of other nations like China, India, and other developing countries with a growing appetite for cheap (dirty) fuel. Also, compromises might have made the bill weak to the point that major carbon polluters would be able to cut down on emissions simply by improving efficiency rather than transitioning to new technologies, which means clean energy sources like wind and solar power wouldn't get much of a leg up. So while the idea was to work within the market to promote a change in our energy economy -- an idea that should appeal to free market conservatives -- the results might have been disappointing, and insufficient.

A new proposal, released jointly from the conservative American Enterprise Institute and the progressive Brookings Institution, calls for an increase in annual federal investment for clean energy research to the tune of $25 billion, up from only $4 billion a year now. A key aspect of the new plan would stipulate that the money only go to programs that are actually reducing the cost of clean energy alternatives. That's important, because we can't realistically expect individuals, companies or other countries to spend much more than their neighbors on clean energy sources just because they want to do their part to help the environment. Many of us want to do our part, but we can't all spend tens of thousands of dollars rigging our houses with solar panels, or $40,000 on the new Chevy Volt.

If the technology can be produced and consumed at competitive prices, though, everything changes.
While we've had solar power technology for decades, the high cost of photovoltaic cells has kept it from competing with coal and oil. This problem isn't easily solved, but more government funding will help companies work with experimental technologies that will be the key to reducing costs. From the consumer's perspective, it's all about price and availability. There's a big difference between asking people to recycle, which is free, and asking them to spend thousands of dollars more for electric cars or solar panels on the roof. Solar panels, electric and hybrid cars all need to come down in price significantly before we can expect a large section of the population to opt for them.

We as consumers have no direct control over emissions standards, but if every car were required to get 70 miles to the gallon, there would be no choice. We would all be driving them, and carbon emissions would be reduced considerably. Or if every car were an electric car, we would all be driving those. Nostalgia for muscle cars aside, few of us lament the improvements made in fuel economy over the last several decades. Fewer of us long for the days when leaded gasoline was the standard. If automobiles can be cleaner and more efficient, there won't be many complaints. But there is little impetus for the car companies to self-impose such measures; there must be an external force of some kind. An oil crisis or a widespread boycott might do the trick, but short of that, only the government has the capacity to set higher standards. Conservatives worry that the government will impose stiff regulations that stifle business, but if every company is in the same boat, I suspect they will find a way to compete. There will always be a market for transportation, and if it's a choice between meeting higher standards and not doing business in the United States, most companies will choose the former.

Even so, there is a legitimate debate over whether we achieve better results by imposing rigorous standards for progress, or by stimulating innovation to desired ends with government funding. The case for the latter is clear: government investment has been responsible for the development of powerful, world-changing technology, like the internet and communications satellites, and as Leonhardt quotes one sponsor of the new proposal, “We didn’t tax typewriters to get the computer. We didn’t tax telegraphs to get telephones." Superior products will eventually win out, and harnessing the infinitely abundant energy of the wind and the Sun is clearly superior to drilling and mining for finite resources. The difference with climate change is, we don't have all the time in the world. We wouldn't be facing a global calamity had it taken another 100 years to get to the computer or the telephone, but we will be facing a global calamity if we wait for market forces alone to change our energy consumption habits.

Reasonable people can disagree on the way forward, but the key is, government has to do something. It's the only entity that has the power to steer the unconscious group-think of the market. But regardless of what you think climate change legislation should look like, the first step is making sure the politicians we elect, Republicans or Democrats, actually believe in climate change. Without that, you can count on seeing precisely nothing done on this issue.

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Another Amateur Space Balloon! Amazing Footage!

2010-10-08T15:40:00.011-04:00

A few months ago I posted a great video from a homemade weather balloon that went 24 miles high. That one's got a pretty feel-good soundtrack and some nice stop motion work, and they captured some wonderful images. But they were mainly just stills, taken with a pair of second hand digital cameras.

Well, I think this video may top that one. Back in August, a father and son from Brooklyn sent up their own weather balloon, equipped with an HD camcorder and GPS. The footage they got is just fantastic. Take a look:

Homemade Spacecraft from Luke Geissbuhler on Vimeo.

My favorite moment is the popping of the balloon, around 19 miles high (at that height they estimate its diameter to be more than 18 feet!), and the tumble back towards Earth. What a spectacular view! This is what Felix Baumgartner will be seeing as he makes his supersonic freefall from the edge of space.

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New Poll, and Twitter Page!

2010-10-07T10:55:00.013-04:00

Our last poll was wildly successful. So let's do it again! If you could fly only one mission to look for life in our Solar System, where would you send it? I've listed some good places to look, but if your choice is not listed, vote for 'other' and leave your choice in the comments section of this post. (The poll is on the right side of this page).

Also, I've decided to try out twitter. I'm a novice, so forgive me if I don't follow protocol right away. But if you're into this whole twitter thing, follow me! I promise to get better at it.

Excitement for the First 'Goldilocks' Exoplanet

2010-10-01T14:55:00.018-04:00

If you were online yesterday, you probably saw the big news in exoplanetology: astronomers have found the first rocky exoplanet that orbits its star in the Habitable Zone, the narrow band of space where it's possible for liquid water to exist on the surface of a planet. This zone is affectionately known as the Goldilocks Zone, because it is neither too hot nor too cold... it's just right.

Exoplanetology is such a young field that we get to experience new "firsts" all the time. It certainly is an exciting time in astronomy. There was the first exoplanet discovered, then the first rocky planet discovered, then the first planet to be photographed, then the first planet to have been discovered with photography. Now we have a new one: the first planet that could be habitable.

("Habitable" in this case just refers to the planet's rocky composition and its potential for liquid water. On Earth, of course, it takes more than just water to keep us alive. Extraterrestrial life, if it is very different from life on Earth, could have radically different requirements for survival. Planets where liquid water is possible are good places to start looking, but we should be careful not to conflate this potential for liquid water with being Earth-like in the general sense, i.e. a place where humans could live comfortably).

Gliese 581g is thought to be about 3 to 4 times the mass of Earth, and probably about 1.3 to 2 times as large. Its surface gravity would be somewhere between 1.1 and 1.7 times that of the Earth, which would be enough to sustain some kind of atmosphere. It orbits a dim red dwarf star, which puts out much less energy than our own Sun. But it orbits much closer, with an orbital period of only 37 days, so the energy output of the star is sufficient to allow for liquid water on the surface. Average temperatures have been estimated to be in the range of -84 to -49 degrees Fahrenheit, but since the planet is tidally locked, with one side permanently facing the star and the other side in permanent shadow, temperatures may range from extremely cold to scorching hot. Much will depend on the nature of its atmosphere... if it has an atmosphere. Astronomers have suggested that life could find a happy medium temperature somewhere near the terminator, where light meets darkness. But an atmosphere of sufficient thickness and appropriate composition could be capable of distributing the heat more evenly about the planet, warming the dark regions.

Amusingly, the media always manages to distort discoveries like these, and yesterday was no exception.
The most egregious of these distortions is that "potentially habitable planet" becomes simply "habitable planet"... a big leap. A decidedly Earth-like rendering published in the New York Times and elsewhere (pictured above) certainly fed the notion that this is Earth 2.0 . And it probably didn't help that one of the planet's discoverers, Steven Vogt of the University of California, Santa Cruz, told the media he thought the chances of life existing on Gliese 581g was "100 percent." He's not talking about intelligent life, of course; simple organisms like bacteria would count. Even so, it's quite a statement... but I won't begrudge him his excitement.

The reality is, we still know very little about this planet. We don't know anything about its atmosphere, so even though it orbits in the Goldilocks Zone, it could have an atmosphere something like that of Venus, with crushing pressures and extremely high temperatures. Or, it could be devoid of any substantial atmosphere, like our Moon (let us not forget, the Moon also lies in the Sun's habitable zone). If the planet has no magnetosphere (like Mars), life as we know it could be impossible, as the solar wind could strip away the atmosphere and make liquid water impossible. The good news is, Gliese 581g is massive enough that a magnetosphere could be present, despite its slow rotation. And a runaway greenhouse effect, like the one that may have brought Venus to its present state, is less likely in the habitable zone. But there are still lots of unknowns.

What is exciting about this discovery is not that Gliese 581g is the second Earth we've been looking for, but that its discovery suggests there are many more like it to be discovered! Red dwarf stars are the most common in the galaxy, and are extremely long-lived (some red dwarfs may have the potential to burn for trillions of years... longer, by far, than the present age of the Universe). It was once thought that life was unlikely around red dwarfs, but as the science is now suggesting otherwise, we have lots of new places to look. Gliese 581 is also pretty close by, only about 20 light years away. That means that if there were an advanced civilization there, with radio astronomy, we could send them a message and receive an answer in less than one human lifetime (unfortunately, visiting Gliese 581 is out of the question for the moment... traveling at the speed of our fastest spacecraft it would take us more than 1.5 million years to get there). The chances of having a civilization there with which we could communicate is remote, but it's nice to know the system is relatively nearby... in a galaxy 100,000 light years across, 20 light years feels like just a stone's throw away.

It's unfortunate that the media has to sensationalize the story to get the attention of the general public. It may or may not be intentional, but we know the discovery is already exciting enough without having to oversell it. For what it's worth, though, any press for exoplanetology is good press. And anyway, even if we temper our expectations of this particular world, we can still relish its implications. With more than 450 exoplanets discovered in the last 15 years -- and that number is sure to skyrocket as more sensitive technology comes online -- we are coming closer to finding worlds that are indeed Earth-like, which in turn brings us closer to finding life beyond our solar system. The possibilities are tantalizing.

Druyan, Breitbart, and the Persistence of Climate Change Misinformation

2010-09-28T11:50:00.039-04:00

Last night, while I was watching Real Time with Bill Maher, I was pleased to see his round table included Ann Druyan, widow of Carl Sagan and collaborator on several of his projects. She and Sagan were responsible for the Golden Record aboard the Voyager spacecraft, carrying the sounds of the Earth beyond our Solar System. She also co-wrote two books with Sagan -- Comet and Shadows of our Forgotten Ancestors -- and contributed to parts of a third, The Demon-Haunted World. Druyan worked with her husband on the monumental PBS series Cosmos, and these days she is president of the Board of Directors for the National Organization for the Reform of Marijuana Laws (NORML).

The other participants in the round table discussion were Family Guy creator Seth McFarlane, conservative radio host Amy Holmes, and the nearly-intolerable Andrew Breitbart.

As the conversation came around to climate change, Breitbart let loose with the now-debunked criticism of the scientists at the University of East Anglia, site of the so-called "Climategate" scandal. Unfortunately, it seemed like Ann Druyan was not quite prepared to start barking at Breitbart to refute his claims, so the dogmatic right-winger got away mostly unscathed. She is, of course, eminently capable of having the argument, but it's not so easy fighting an attack dog on national television... especially on a comedy show. Perhaps she might have said something like this, had she ample breathing room to get it out of her mouth:

Science deniers love to cherry pick, and the controversy at East Anglia is a great example of this. Not only do they not fully understand the science involved, but they also prefer to home in on a few instances of questionable science and extrapolate that to suggest that the whole of climate change science is false. That's classic conspiracy theory thinking, and it's illogical. It's sort of like taking the math test from the one student who got an answer wrong, holding it up next to all the other tests of the students who got the problem right, and claiming that there's a debate as to what the right answer really is. In my formative years I got lots of math questions wrong, but I never tried to claim that the answer was open to debate. I just had to acknowledge that my math was wrong.

The basic accusations against the scientists at East Anglia are these: that they fudged their data and/or their math to reflect a predetermined result; and that they deliberately suppressed the views of scientists who questioned the theory of human-driven climate change. These are serious charges, but fortunately, they don't hold water. The accusation that the scientists improperly manipulated their numbers comes from one e-mail exchange, in which there is reference to a statistical "trick" that is used to make two sets of data line up with each other. It sounds like they're manipulating the data, but that "trick" simply refers to a method for working with numbers, no more sinister than the concept of "cross-multiplying." And the allegations of suppressing the views of scientists with alternative views -- as Breitbart echoed on Real Time -- have been shown to be unsubstantiated, months ago.

In any case, clearly erroneous conclusions, like the ones discussed in some of the controversial e-mails, simply should not be published. It's not a matter of covering up data. Suppose you were doing some math problems with the aid of a calculator, and your answers came out like this:

1 + 9 = 10
2 + 8 = 10
3 + 7 = 10
4 + 6 = 10
5 + 5 = 10
6 + 4 = 2

Woah, what happened there? Something is clearly amiss. You know that 6 + 4 should equal 10, but your screen says 2, and you're pretty sure the laws of mathematics aren't breaking down before your eyes. Obviously, you hit SUBTRACT when you meant to hit ADD. This is easy to see, but when you're using statistical models and complex sets of data, the error may not be so easy to discern. You know what the right answer should be, but you keep getting the answer wrong. Like any struggling math student, you'll turn to a colleague and compare answers, and try to figure out what's gone wrong. This is not the same thing as manipulating data to reach a predetermined conclusion.

Now, imagine you have a vocal minority of people in the world who are hell-bent on proving that math is a questionable field, that there is reason to doubt it. Imagine that the fate of the planet rests in the balance. And imagine that your wrong answer on the math test is going to be used as evidence to support the case of the math-deniers. You probably wouldn't want your calculations to be made public.

Such is the case for climate change scientists. The deniers are scrutinizing their work for any sign that the whole field is hogwash. Unfortunately, there is extreme pressure on these scientists -- not from the science community, but from the external forces seeking to undermine their work -- and that pressure can lead them to be more reticent about sharing their data. Under the Freedom of Information Act in the United Kingdom, climate change skeptics can badger climate scientists with requests for data, and the climatologists are required to respond within 20 days. It's easy to see how excessive requests could be a hindrance to the actual work of the climate scientists, and in the adversarial spirit of this conflict, poor decisions about data sharing could be made. Contrary to what the critics maintain, though, debate is encouraged in the scientific community. It's the only way we can advance our knowledge! But for those who don't trust science, that little detail tends to go unnoticed.

("Debate" here is a very broad term, and it should be pointed out that not all dissension is created equal. Some questions are still debated in the scientific community, and good scientists can disagree; for instance, "how exactly did life arise on Earth?" There are various hypotheses, and we await more evidence to nail it down. Conversely, there is no question as to whether the Earth goes around the Sun. Someone may come along and claim that the Sun revolves around the Earth, but his or her views could not be reconciled with the data. There is no debate here, this "scientist's" claims can be dismissed out of hand. This is not to say that there are no questions left when it comes to climate change, but rather that challenges to climate change theory have to be legitimate ones, not ones based on an agenda or faulty science).

Evidence should never be suppressed or covered up, and the scientists at East Anglia were certainly clumsy with the way they spoke about their number problems and data sharing; though, since they never expected the e-mails to be made public, it's only natural that they thought fellow scientists would understand their problem and read it in the proper context. But climate change deniers thrive on taking things out of context, so the scientists rightly feared that their numbers would be used as ammunition against them and their field... just look what happened!

As the East Anglia controversy fades from our collective memory, you can bet the climate change skeptics will remember it and continue to cite it. It doesn't matter that five separate panels have cleared the scientists of wrongdoing. These are details you'll only get by reading the lengthy wikipedia article. I suspect Breitbart's audience, or Sean Hannity's audience, or Sarah Palin's audience, won't get through the whole thing. Or if they do, they'll cherry pick their facts.

The Private Sector in Space

2010-09-24T14:07:00.015-04:00

Check out this rundown of the burgeoning companies who want to get in on the private space industry, courtesy of NBC.

President Obama's plan for the future of NASA has been controversial, to say the least. Amazingly, his plan has received considerable attention in the media, and it seems like just about everyone -- informed and uninformed alike -- has weighed in. I say 'amazingly' because by and the large the American public, or at least the powers that be, really haven't seemed to care much about our manned spaceflight since 1972, except when there has been a tragedy. True, we like seeing our astronauts wave hello to the Colbert Nation, or wave hello to a classroom of school kids, or wave hello to Wolf Blitzer. But the enthusiasm and can-do optimism that carried men to the Moon largely evaporated in the wake of the Moon race, and has never really come back.

It may have been inevitable. The public interest waned, Mars was considerably more difficult to reach, and maintaining expenditures at the level of the 1960s was impossible to justify. There was really no need to keep pushing a manned project of that magnitude, anyway, now that we had beaten the Russians to the Moon. But we knew the Soviets were working on space stations for the purpose of spying on the United States, so yet again our space ambitions were tempered, or driven, by our national security interests. We put up Skylab with the leftover parts from the Apollo program, and Nixon authorized construction of the Space Shuttle. And now, almost forty years later, we're still hanging out exclusively in Earth's orbital parking lot. It's funny how time flies.

Manned spaceflight today, shuttling to and from low-Earth orbit, is not exactly routine. But it is in the minds of most Americans. Which is why I was somewhat puzzled by all the negative reactions to President Obama's plan. (Curiously, the critics of the President's plan have not advocated a dramatic increase in NASA's budget, which might preclude the need for a shuffling of priorities).

There are several facets to the plan, of course. Part of it calls for more money to go to unmanned science missions... the kinds of missions that have shown us some of the most dazzling sights of our solar system, and revealed all kinds of wonders in the depths of interstellar and intergalactic space. Part of it calls for building a spacecraft that can take us much deeper into space, to land astronauts on an asteroid (an unimaginable journey!), and then on to Mars. But the part that has been most controversial is the plan to farm out these "routine" orbital missions to private companies.

The apprehension is understandable, but it's not necessarily warranted.
Look at all these companies revving up and ready to go! If the whole plan were to rely on one or two companies for these space taxi services, that might be reason for concern (although, that's essentially what we'll be doing when we pay the Russians for a ride up to the ISS after the retirement of the Space Shuttle). But with all these groups getting into the game and ready to compete for contracts, a whole new industry is taking shape, so there's no reason to think that we can't fly these missions at a lower cost, and help stimulate the next phase of our space exploration at the same time. Private sector involvement is the next logical step in the progression of technology... first the government develops it, when costs are prohibitive, and then the private sector comes in and makes it cheaper and more consumer-friendly. Such was the evolution of the internet, and communications satellites.

Change can be painful, and there may be some jobs lost, or shifted elsewhere. Some of those technicians who work for NASA and have a vested interest in the status quo may have to relocate. There is some risk of a brain drain, whereby the expertise gained over 50 years of spaceflight is lost in the transition. But these sorts of changes are inevitable, and should not be reason to restrict progress. Inevitably, the demand for equine accessories dropped off dramatically when the automobile became mainstream. Ocean liners had to adjust their business models when trans-Atlantic air travel became routine. And one day, we hope, the demand for oil and coal will decline radically as we transition to a clean energy economy. As sympathetic as we may be to the hardships endured by those working in a withering or antiquated market, we just can't allow that to stifle our progress overall.

Hopefully, though, the NASA engineers won't be out of job. There will still be a need for their expertise in the private sector. So we probably shouldn't worry too much about them.

Of course, this whole thing could turn out to be a total disaster, especially since Congress has a peculiar talent for turning good ideas into horribly misguided policies. But let's all just take a breath and see how it goes. If things don't go as planned, we can always go back and do it the old way.

Racing for the Supersonic Space Jump

2010-09-23T16:07:00.014-04:00

Be sure to check out this fantastic piece from The Guardian which is, I think, the best profile I've read on the Red Bull Stratos project. As we've discussed a few times before, the Stratos project aims to make skydiver Felix Baumgartner the first man to break the sound barrier as he falls from the edge of space, at a height of 120,000 feet above the surface of the Earth. A jump of this type has not been successful since Joseph Kittinger made his historic and daring jump from 102,800 feet in 1960. But Baumgartner, jumping from 17,200 feet higher, will be the first man to break the sound barrier in this way.

Or will he? The Guardian tells us about another daredevil devoted to the task. He is Michel Fournier, a 66 year old former paratrooper from France, and since the 1980s he's had his sights on breaking the sound barrier with a space jump of his own. Unlike Baumgartner, there is no corporate sponsorship for Fournier, so he has invested millions of dollars on the project, all from private donations and his own pockets. Several previous attempts have been thwarted by technical difficulties, but he plans to make another attempt in the next couple of months... around the same time that Baumgartner is expected to make his jump.

I don't know him personally of course, but Felix Baumgartner seems like a pretty awesome dude, with a cool name to boot. I've followed this story for months, and I've been eagerly anticipating his jump. Even so, I wouldn't mind seeing Fournier beat him to the punch. It's sort of a David versus Goliath story... or Little Mac versus Mike Tyson, or Little Jerry versus Marcelino's bird, or Bill Paxton versus Cary Elwes (use whichever reference you like best). Except, of course, that Baumgartner is not so much an enemy as simply a better-funded competitor. And for his part, Fournier is gracious about Baumgartner's chances of beating him to the supersonic skydive: "I'll congratulate him. But you can bet that I'll do it second."

Let's just hope he can do it safely. Fournier hasn't exactly been on a shoestring budget, but he does lack the team of experts, training facilities and spare-no-expense equipment of his competition. The jump itself is extraordinarily hazardous, and no one knows for sure what will happen when a human being breaks the sound barrier with his body. But if he succeeds, even in second place, Fournier's accomplishment will be equally astounding, perhaps more so. And now we have two space jumps to anticipate!

New Record in Ornithopter Flight!

2010-09-23T13:55:00.010-04:00

Well, here's something you don't see everyday. Back in August, grad student Todd Reichert from The University of Toronto set a new record for the longest flight of an ornithopter powered by a human being. The aircraft weighs just 94 pounds and has a 32 meter wingspan!

HPO The Snowbird from U of T Engineering on Vimeo.

As its name suggests, the ornithopter is an aircraft that flaps its wings like a bird, and as you can see in the video, it needed a little help from a car towing it to get it going. But once in the air, the flapping wings took over, and the craft flew for a record 19.3 seconds.

Something tells me we won't see commercial ornithopter flights anytime soon. But it certainly is a graceful aircraft, don't you think? And in seeing how difficult it is for us humans to achieve flight in this way -- you need extremely light-weight materials, an enormous wing to payload ratio, and a tow to get it aloft -- we can appreciate the exquisite gift of flight enjoyed by our cousins, the birds... a gift bestowed on them by evolution.

ARTEMIS goes to the Moon, Meets Lagrangian Points

2010-09-15T15:44:00.006-04:00

I love Lagrangian points!

NASA has achieved another first for spaceflight... the first orbit around a Lagrangian point, or libration point. Unlike all other satellites, the ARTEMIS spacecraft is actually orbiting an area of empty space! These orbits aren't entirely stable, so they'll require a little maintenance. Still, this is a cool thing. Check out the unusual, kidney-like shape of the orbit.

Lagrangian points are a neat little trick of gravity. There are five points in a two-body system (like the Sun-Earth system, or the Earth-Moon system) where you can place a third body of negligible mass and it can remain stationary relative to the other two. The second Lagrangian point of the Sun-Earth system (not to be confused with the Earth-Moon system's L2, pictured above) is about 1.5 million kilometers away, and is the future home of the much anticipated James Webb Space Telescope, which will be launched in 2014. And the fourth and fifth Lagrangian points on either side of Jupiter are home to a special class of asteroids known as Trojans.

Nice work, JPL.

Look Around You - Maths

2010-09-10T10:07:00.003-04:00

If you're a regular reader, you may have noticed a decline in the number of posts recently. Well, it's the start of the semester, so it's a very busy time at my real job. But don't worry, I expect to be back to business as usual in a week or so. In the meantime, please enjoy this splendid parody from Robert Popper and Peter Serafinowicz:

Asteroid Discoveries, 1980 - 2010

2010-08-30T11:58:00.022-04:00

Check out this fantastic new video, which shows all of the asteroids in a time lapse as they were discovered over the last 30 years. In the bottom left corner, you can see the year and the number of asteroids steadily climbing:

Notice the huge increase in discoveries towards the end of the 1990s. That's thanks to automated systems like the LINEAR project, which has discovered over 226,000 objects since its inception. Like most illustrations of the solar system, though, this animation is not drawn to scale; the Main Belt look crowded here, but the actual distances between the asteroids are still very large.

I like to think about asteroids. There are so many of them, far more than can probably ever be named. They can seem commonplace and, compared to the pantheon of the planets, they may be mere afterthoughts. They tumble slowly through the blackness of space, utterly unaware of themselves, drifting endlessly on their lone path around the Sun, gently tugged by something or other over the eons. Nothing drives them but the elegant machinery of the universe.

Occasionally two of these austere mountains will meet each other on the lonely road, smash into each other, and cast their smithereens in all directions. Some of those bits may find their way to the Earth, burn up as they rocket to the ground or, astonishingly, survive the trip and end up in a field in Maine, or a car roof in Rome. They will be studied or sold, and put on display. And we know that these rocks are hearty travelers, so we can handle them.

Whenever I get the chance to hold a meteorite I think about how it got here. This small, heavy iron rock is just a tiny fragment of an enormous primordial monolith, and there’s no telling how long ago it was utterly destroyed – or at least transformed radically. Its precise history is unknowable, but its lineage is as ancient as our own.

The asteroids have orbited lazily since the birth of our solar system, intermittently disturbed, and sometimes pieces of them, quite by accident, end up here. But until their fiery arrivals here on Earth, these rocks had known only cold nothingness for billions of years. A rock from the sky reminds me how empty and lonely it is in the vast depths of interplanetary space, to say nothing of the inconceivable distances to our neighboring suns. In realizing how helplessly isolated we are from the friends that may await us among the stars, we can begin to understand at last the preciousness of our fragile world, and the imperative of its protection.

Intelligent Machines and the Search For Extraterrestrial Life

2010-08-24T09:32:00.046-04:00

SETI astronomer Seth Shostak has a novel idea: let's look for signs of extraterrestrial Artificial Intelligence, rather than focusing exclusively on the search for biological life. If we were to take his advice, this could mean searching for signs of intelligence around the galactic core and hot young stars, in addition to observing the stable, middle-aged stars like our Sun. We would typically think these young stars are unlikely to have life in their systems (since there has not been enough time for the evolution of complex beings), but they could be attractive destinations for smart machines wanting to soak up the abundant energy given off by these energetic youngsters.

It seems like a great idea, and I wonder why I haven't heard it before. Of course the idea of encountering alien AI in space is nothing new... some scientists even think that somewhere out there there may be aliens who have transformed themselves into intelligent machines. That may sound strange, but with the advent of hearing aids, artificial limbs, pacemakers, and even bionic eyes, futurists have long wondered how far we humans will go in transforming ourselves with technology -- becoming more and more like cyborgs, integrating machinery into our bodies until we are more machine than man, and perhaps one day shedding our biological vehicles altogether, transferring only our consciousness to a super computer. Maybe then we will live in a robot civilization, or perhaps our bodies will be spaceships, and we will travel between the stars for ages, powered by nuclear fusion, or some exceedingly remote technology. These might be our distant relatives, maybe resembling something like the Voyager spacecraft drifting endlessly in the darkness, except that they might still harbor a pioneering spirit carried on from humankind, and some notion of whence they came.

The idea of turning ourselves into machines isn’t exactly heartwarming, but it does have its advantages. Machines could live much longer in space than our fragile bodies. Life support is extraordinarily economical with no food or potables to carry. The vast distances between the stars can be traversed without the human problem of aging, and without the relativistic tragedy of rushing fast into the future and leaving a family behind forever. And of course turning ourselves into spacecraft would mean the capacity to survive a catastrophic event on Earth, like a monstrous cometary collision or the eventual death of our Sun.

Whether we’re looking for extraterrestrials who have become machines, or just the artifacts of extraterrestrials, it really just becomes a question of odds. On the one hand, we’re opening up new avenues of exploration, thinking about ways to find life (or intelligence) as we don’t know it, and that would seem to increase our chances of finding something. But at the same time, we’re diluting the resources. In other words, the more kinds of intelligence signatures we look for, the less time we can devote to each, and since SETI is now funded primarily by private sources, telescope time is at a premium. That’s probably why Shostak is suggesting we look for these other things only a few percent of the time.

But what are we more likely to find, biological life forms, or their technological offshoots? The case for the latter is compelling. Shostak uses the Drake Equation as his jumping-off point, taking for granted an inevitable leap into Artificial Intelligence technology for advanced civilizations. If these smart machines are able to outlast their inventors, he argues, then statistically it's more likely that we will encounter them. But even neglecting these calculations, it is a good bet that we might encounter some kind of artificial, space-faring sign of intelligence. For reasons mentioned above, it makes a lot of sense to send robotic emissaries into space on behalf of a biological species. We’ve been doing it for years: for relatively little cost, we’ve sent robots to do our bidding across the solar system, and their recon work is superb. They can spend years speeding through the dark, a job which, until we master hibernation, would be maddening for humans. And we don’t feel too bad about not giving them enough propellant to return to Earth. We’ve now got four spacecraft (five if you include New Horizons) on their way out of the Solar System, and it’s likely there will be more to come. A civilization far more advanced than ours could have robotic spacecraft flocking through the galaxy, perhaps equipped with their own radio telescopes, plumbing the depths of space in search of other voices. Such an advanced civilization could extend its reaches far beyond its home world, creating an outsized presence that could be easier to detect.

We should be careful not to get ahead of ourselves, though. There is already a high bar set for interstellar communication: the civilization has to have radio astronomy. This is no little problem, because we’ve only had it for about 75 years or so. But there was no shortage of interesting people to talk to here on Earth before the 1930s. Modern civilization stretches back thousands of years, and complex life is billions of years old! But until the 20th century, from a cosmic perspective we were a silent world. Obviously, a silent world is not necessarily an uninhabited world. An alien civilization (depending on their experience, I guess) would probably have been just thrilled to find the trilobites scurrying around on our planet 400 million years ago, or the dinosaurs stomping about 70 million years ago; but such a discovery would almost certainly have been an accident. Our astronomers would be ecstatic to find even a fossilized microorganism on Mars, so you can imagine what the discovery of any living, complex organism would be like. The capacity for interstellar communication is not a requisite for being an interesting planet, or species. But if there are dinosaur analogs on a planet orbiting a star just a few light-years away, there’s no way for us to hear from them. There may be many such worlds nearby, teeming with living wonders but utterly cut off from the universe. Short of an expedition, or definitive evidence from a spectroscopic analysis of the planet, we will have no clue as to what resides there.

As soon as we start raising the bar for the technology of extraterrestrials, we run the risk of missing other civilizations that might not be quite as advanced. It’s exciting to think about alien machines huddled around hot young stars and harvesting that massive energy for their futuristic business, but for the moment, looking for life the old fashion way might still be best. And even if there are robots operating with technology thousands or millions of years ahead of ours, I suspect they'll still be able to recognize our signals. Hopefully, we'll be able to recognize theirs.

Richard Hoagland, Pseudoscience and the 2012 Doomsday Prophecies

2010-08-18T15:22:00.027-04:00

A reader writes:
Did you see the documentary aired a few weeks ago [on MSNBC]? It was a rerun about those who have studied what everyone believes about what they say will really happen on Dec 20th 2012 Mayan calendar. Even the remaining Mayans are almost sorry people know about it. Me I am more inclined to believe what Richard C. Hoagland said will happen to our Earth. What do you think or have found out anything new on this?

I’m afraid I missed this particular program on MSNBC, but I have seen several shows on the same subject, particularly on The History Channel. Unfortunately, these programs tend to lend more credence to these theories than they really deserve, alternating between interviews with scientists and fringe thinkers as though the evidence is equally compelling on both sides (for a succinct refutation of the various 2012 claims, check out NASA’s page devoted to it here).

I am not very familiar with Richard Hoagland’s views on the Mayan Calendar / 2012 Doomsday Prophecy, but a little research on his background will tell you this gentleman’s claims are suspect. Mr. Hoagland is a proponent of multiple space-based conspiracy theories. For instance, he believes that the United States government is covering up evidence of ancient alien civilizations on the Moon and on Mars. In his view, not only has the photographic evidence been suppressed, but the 12 Apollo astronauts who set foot on the Moon were actually hypnotized upon their return to Earth, so that they have no memory of seeing the semi-transparent structures he claims are all over the surface. Mr. Hoagland also believes that a sect of Nazis escaped into space following World War II, and has been operating there ever since, with superior technology to our own. According to Mr. Hoagland, fears of these space Nazis convinced President Obama to abandon the Constellation program. Mr. Hoagland also believes that Mars’ small moon Phobos is actually an enormous, decaying alien spaceship, and he is a major supporter of the Face on Mars theory.

Let’s be honest. Conspiracy theories are a lot of fun to think about. We have a natural affinity for the idea that the world we see is really just an illusion, that there may be some clandestine underpinning, perhaps with malevolent purposes, and that we are one of the few people able to see beyond the smoke and mirrors. This theme is prominent in many fantastic dystopian films, like The Matrix or Dark City, or one of my favorites, Soylent Green. For years people have speculated about a conspiracy surrounding the assassination of John F. Kennedy, and a popular film like JFK can easily whip up a fresh batch of skepticism over the official account. And of course, we know that many governments around the world really do engage in some covert activity, so it’s only natural to wonder how deep the rabbit hole goes.

The problem is, while most of us dismiss these more outlandish conspiracy theories as little more than entertaining ways of looking at the world, to the conspiracy theorist, or the person falling victim to pseudoscience, these are real world problems that must be solved. In extreme cases some of these people could even develop a Cassandra complex, believing that they alone see the truth and that the rest of us are drones, skipping along happily, ignorant of the dark reality of our lives. And in this respect, sensationalist programming can do a disservice to the general population. They can fill susceptible minds with unfounded fears, and undermine legitimate science. After all, if these scientists are so blind to the coming apocalypse just two years from now, what else do they not know? Can we trust vaccines? Does global warming really exist?

It may be that some conspiracy theories really are true. As a matter of course, these scenarios if real would leave behind little evidence, as the proof would have been necessarily destroyed. But when we come across a career conspiracy theorist like Mr. Hoagland, we should be even more skeptical, because if his livelihood depends on propagating new theories about government secrets and alien civilizations, he would be well advised to come up with new ones all the time.

As Carl Sagan was fond of saying, extraordinary claims require extraordinary evidence. The reality is, scientists would be thrilled to discover evidence of life on the Moon or on Mars, and it would be enormously difficult to keep such an astonishing discovery secret. If Phobos really were a dilapidated alien spacecraft, you can be assured that NASA would want to go investigate it (and even if the exact nature of the project were kept secret, the powers that be would probably be pursuing an overt mission to Mars much more aggressively). Would we like there to be an unknown reptile of large dimensions, a relic of the cretaceous period perhaps, swimming around in Loch Ness? Of course we would! And we’re open to convincing evidence. But a few hazy photographs that are easily faked will not suffice.

Mr. Hoagland’s claims may be imaginative, but they don’t hold up to scrutiny. Indeed, much of the evidence for his claims relies on his other unverifiable theories. He puts together an interesting concoction of old and new ideas, blending space Nazis with UFOs and even 9/11 conspiracy theories. But the photographs he uses to support his theories are usually inconclusive or doctored, and the connections he draws between otherwise ordinary events are tenuous and far-fetched.

More to the point, nothing we know of in the solar system or galaxy gives any indication that the 2012 Doomsday prophecy holds water. The theories are, once again, a wild mix of various ideas, based on cryptic or misconstrued passages from old texts, astrology, numerology, and faulty science. Of course some apocalyptic scenarios are plausible, if very unlikely: an as-yet undiscovered asteroid could slam into the Earth, or a nuclear war could break out. But if nothing happens, as I suspect will be the case, these fringe thinkers won’t go out of business. Rather, they’ll simply recalculate, or explain away their error. They’ll say the world is really going to end in 2020, perhaps, or say that some flood in Siberia is the event Nostradamus was really predicting.... but that another passage is far more ominous. Doomsday predictions have been common throughout history, but of course none of them have ever come true.

Many fundamentalist Christians believe that we are living in the End Times, and that the apocalypse is eminent. For them, this may be a moment to celebrate, and the 2012 predictions may feed their excitement. As for me, I do fear an unanticipated asteroid collision, as well as the madness that might ensue from a nuclear detonation. But rather than subscribing to mysticism and fatalism, we can rely on science and diplomacy to help us avoid these possibilities. They're not perfect tools, but they're a lot better than the alternative.

I'd love to hear from you! Please feel free to write me at tychocrater@rocketmail.com with any questions or comments.

Back From Holiday!

2010-08-16T14:41:00.021-04:00

I'm catching up on work for my real job today, but I wanted to share with you a picture of the Milky Way I snapped while I was gone. Take a look:

This photo was taken on my Nikon D5000 with a 30 second exposure, wide aperture and 3200 ISO. Brightness and contrast have been manipulated to highlight detail.

I spent the evenings looking at the Milky Way in the southern sky, observing Venus half-lit and Saturn in the west around twilight, and Jupiter rising later in the eastern sky. We could see a distinct band of red clouds around Jupiter, and the four Galilean satellites shining brilliantly. One night, I was thrilled to see an object that I took to be Amalthea (Jupiter V), a small moon interior to the big four, discovered by E. E. Barnard in 1892. It was the highlight of my observations, but I'm forced to confront the possibility that it may have been just a faint background star, as the moon's apparent magnitude seems to be just a hair beyond my telescope's theoretical limits (the other 58 known moons of Jupiter are far too faint to be seen in my modest reflector). It's possible that Amalthea is really what I saw, but I'm afraid the evidence is not conclusive. Ah well.

Unfortunately, the transit of Jupiter's Great Red Spot came at inconvenient times, but of course the Perseid meteor shower was a delight. We were fortunate to have dark skies, though by the end of the week the crescent Moon had begun to creep up in the west.

If it's a clear sky tonight, take a look up.

Vacation!

2010-08-06T10:35:00.002-04:00

Going on vacation with my family this coming week, so I'm afraid there won't be any updates while I'm away. Check back here around the 16th. Thanks for reading!

Citizen Scientists Analyze Stardust Data

2010-08-03T10:26:00.006-04:00

The New York Times offers this piece on the citizen science project that's studying the results of the Stardust mission, helping scientists find tiny particles from interstellar space.

This project, known as Stardust@Home, is part of what seems to be a growing movement of non-professional involvement in analyzing vast amounts of scientific data. MoonZoo, for instance, has been employing amateur scientists to help analyze mountains of images from the Lunar Reconnaissance Orbiter, and other Zooniverse projects are doing the same thing with galaxies, supernovae, and solar storms.

This is an exciting trend. For one thing, allowing the general public to get involved means increased awareness and excitement for these projects. At the same time, the scientists get some relief from what would otherwise be years of tedious analysis, and regular citizens get to work with data that they would not be able to gather on their own. Putting this work in the hands of citizens also challenges the notion that science is strictly the domain of ivory tower academics.

There is a proud history of amateur astronomers making great contributions to space science. Perhaps the greatest of these was the work of William Herschel, a musician and amateur astronomer (later employed by King George III) who built the most powerful telescopes of his day and discovered Uranus -- the first planet discovered since antiquity. His discovery shocked the scientific establishment of Europe, and he went on to discover two moons of Uranus and pioneer the study of double stars (for more on Herschel and the scientific calamity his discovery caused, I recommend The Neptune File by Tom Standage - out of print, so you'll have to pick up a used copy).

Let's hope these projects continue, and given their success, I think they will. These remarkable collaborations have only become possible in the last few years with the dawn of the internet age... a time when virtually all of our collective knowledge is stored somewhere online, and anyone can read about a topic that once would have been known only to professionals in the field. And anyway, many hands make light work, and when it comes to science, the more the merrier.

Pictured above, from the New York Times: "This scanning transmission X-ray microscope image shows a carbon-rich speck collected by the Stardust spacecraft."

The Rundown - August 2nd, 2010

2010-08-02T14:20:00.019-04:00

Here's what we're watching right now:

A cooling mechanism has malfunctioned aboard the International Space Station, forcing a shutdown of several systems. The astronauts are in no immediate danger, but normal function will not be restored to the station until two emergency spacewalks fix the problem.

A new paper from Wun-Yi Shu at the National Tsing Hua University in Taiwan suggests that the Big Bang model of the universe may be erroneous. According to his cosmology, there is no beginning or end to the universe, and the accelerated expansion of the universe can be explained without dark energy. The theory is not flawless, though... it appears there is no explanation (yet) for the existence of the cosmic microwave background radiation, which is thought to be a left over from the fires of the Big Bang. It also relies on the speed of light being variable, instead of constant as we typically think of it.

Another big surpise: The new report from the National Oceanic and Atmospheric Administration says the 2000s was the hottest decade on record:

The 2009 State of the Climate report released today draws on data for 10 key climate indicators that all point to the same finding: the scientific evidence that our world is warming is unmistakable. More than 300 scientists from 160 research groups in 48 countries contributed to the report, which confirms that the past decade was the warmest on record and that the Earth has been growing warmer over the last 50 years.

The killer asteroid story that splashed across the internet last week apparently came out in a report last year. No one seemed to take much notice back then, but the groupthink of the interwebs has a funny way of turning an old report into breaking news. (In case you missed it, don't worry... the possible impact would not occur until the late 2100s).

IKAROS is sailing smoothly, steering without propellant.

Two satellites from the THEMIS mission are getting a new lease on life, with orders to go study the Moon.

Pictured above, the THEMIS satellites in orbit around Earth.

Creationist Nonsense

2010-07-29T09:30:00.056-04:00

This clip has been around for a while but I've just stumbled on it, and it's so astounding I just had to address it here. Take a look (embedding this video was causing problems).

In all my years, I don't know if I've ever come across a more nonsensical argument against evolution. I'm just itching to write the anti-Creationism treatise I promised a while back, but for now I think I'll just stick to the facts of this case. What in the world are these people talking about?!

While this video may be the most puzzling of approaches to debunking evolution, I'm afraid it's not very far from what many people actually believe. It represents a profound failure of education and imagination, along with an unhealthy dose of blind faith.

This gentleman claims evolution doesn't happen because we don't find life spontaneously generating out of a jar of peanut butter* (a version of this argument also figures prominently in Ben Stein's ludicrous documentary on intelligent design). The implication here is that life can't just come from nowhere... which is what scientists apparently believe, right? No, of course it doesn't come from nowhere. But the situation is much more complex than these Bible-thumpers care to read about.
Experiments have shown that we can make complex organic molecules, the building blocks of DNA and RNA, simply by zapping the constituents of the early atmosphere with electricity, just as lightning would have done on the early Earth. Of course it's not proof that life arose in this way, but it does quash the notion that this sequence of events is somehow unusual or unlikely. Nevertheless, these experiments do not produce any exotic insects, or even single-celled organisms. Why? Because these life forms took billions of years to evolve! Life on Earth is thought to have had far humbler beginnings. In the primordial oceans, many scientists think, there was a rich soup of organic molecules and one day, quite by accident, a molecule arose that was able to make crude copies of itself, using the other molecules in the soup as building blocks. This would have been the ancestor of our DNA molecule.

Does that sound like magic? Well, it is pretty incredible, and it may sound like magic, until we think about the chemistry going on inside our own bodies at this very moment! We know that the DNA molecule unzips itself and makes copies of itself inside our cells. Is there some sort of miniature DNA brain at work here, directing the copy job? Of course not. It's just chemistry. And if the chemistry works today, there's no reason why it shouldn't have worked billions of years ago.

Of course, none of us were around billions of years ago to witness this, and herein may lie the trouble for these true believers (but last time I checked, no one was around to see God take the rib out of Adam and create Eve, either). How can we know these things? Well, science is an amazing thing. We can figure lots of things out, even if we can't go see it with our own eyes. We hypothesize, experiment and deduce, and this has led to some pretty dazzling discoveries. We figured out how objects move in space centuries before we had the technology to go to space and see it in action. We have figured out how to look at the light from planets, in our solar system and beyond, and determine what's in their atmospheres. And we have discovered the origin and age of our universe by discerning the motion of the galaxies and studying the cosmic microwave background radiation -- the faint echo of the Big Bang.

When it comes to evolution, we weren't around to see it all, but we have the fossil record. But we don't even need the fossils to know that evolution really happens! We see it happening all around us even today. For instance, we know that viruses arise that are resistant to vaccines that only recently were perfectly effective. Does this happen because there is some mastermind virus out there, hatching a scheme to get around those annoying vaccines humans create? Of course that's absurd. The viruses which by accident are resistant to the vaccine preferentially survive, and pass on this resistance to their progeny. As these little mutations add up over the generations, new species emerge. Sometimes viruses which once only harmed monkeys evolve to afflict humans, too, which can explain the seemingly spontaneous emergence of horrific diseases. Rather than a scourge of God, science tells us these viruses are mere accidents of natural selection.

Science is not perfect, and some of the things we think we know for sure today may be shown to be fundamentally erroneous in a few years. But science is constantly correcting itself, refining our understanding of our universe. On the other hand, you have your religious text, unchanged for thousands of years, with the marked exception of countless translations that, like the game of telephone, are sure to obscure at least some of its original meaning... perhaps with disastrous effects.

If you really believe that the Bible was dictated by the creator of the universe to an unerring stenographer, and everything within it is the literal truth, you just can't believe the Earth is billions of years old. Instead, you believe the Earth was created somewhere in the range of six thousand years ago. And if you've only got six thousand years to work with, the evolution of everything we see in this world is a pretty tall order. The Bible tells you God created all the life on Earth within one week, and the impossibility of evolution in six thousand years confirms that for you.

Well, if God exists, I think he would want us to use the brains he gave us.

*I didn't want to take up space above, but this example is littered with problems. Why on Earth should new life arise out of a jar of peanut butter, after it's exposed to only neglible heat and light, and after it was processed in a factory? What is the criteria for foodstuff to be a favorable incubator for brand new organisms? If evolution exists, why shouldn't we expect to see life emerging from, say, fresh bananas, or a jar of olive oil? This argument is based on a flawed premise -- matter sparked with energy is not necessarily going to give rise to life. Metal is matter, and we don't expect life to arise from spark plugs. Indeed, everything in the solar system is made of matter... does this mean life must arise even on the inhospitable asteroids for evolution to be proven true? That's a pretty high standard of evidence. Furthermore, why should we start with peanut butter as our early Earth analog, when all indications suggest there was no peanut butter present on Earth 4.5 billion years ago? The Miller-Urey experiment used the substances that were around back then. There is also no clue as to how long exactly we should have to wait for this peanut butter to hatch something like an ant. Hopefully the peanut butter I pick up at the supermarket is fresh enough to avoid such foolishness.

Scientists Developing Artificial Magnetosphere for Interplanetary Exploration

2010-07-28T11:43:00.012-04:00

Scientists at the Rutherford Appleton Laboratory in the United Kingdom are working on an artificial magnetosphere that could protect astronauts on a mission to Mars.

Long duration space flights present a special problem: the charged particles of the solar wind are extremely dangerous to the health of astronauts. On a trip to Mars, astronauts would be exposed to this radiation for months. Heavy shields on the craft would be enormously expensive to lift into space, but what if we could create a miniature magnetosphere, like the one that protects us here on Earth?

The research is still in its early stages, but it's looking like creating a little magnetosphere for a spacecraft is not as daunting as was once thought. You don't need a giant molten iron core... a modestly-sized electromagnet might just do the trick. It turns out that these sorts of small magnetic shields are more common than we thought... even some asteroids have been shown to have them. And as NewScientist explains, the magnetic field doesn't need to be all that powerful:

Some parts of the solar wind shift more easily than others. The positively charged protons have nearly 2000 times the mass of the negatively charged electrons, so the latter are much more easily deflected. The electrons stay at the surface of the magnetic bubble, while the positive charges penetrate further in.

This separation of positive and negative charges generates intense electric fields up to a million times stronger than the magnetic fields that created them. Subsequent solar wind particles hit these electric fields and are strongly deflected. The result is a shielding effect far more powerful than the magnetic field alone might be expected to provide.

We're still a ways from seeing these force fields utilized on spacecraft. But this work brings us one step closer to making a mission to Mars a reality. Very cool.

Are We Living Inside a Black Hole?

2010-07-26T10:55:00.020-04:00

A new paper from cosmologist Nikodem Poplawski examines the relationship between the expansion of our universe and a hypothetical rebound force that might counter gravity inside a black hole. Among the implications, it could mean we're all living inside a black hole.

Come again?

Well, early on in the 20th century we figured out the universe is expanding. Here's a concise history:

We know that light acts as a wave. There are higher frequencies and lower frequencies, which correspond to the different kinds of light (from longest to shortest wavelength: radio, microwave, infrared, visible light, ultraviolet, x-ray and gamma ray). Due to the Doppler Effect, whenever a source of light is moving away from us at a sufficiently high speed, we can discern a redshift, meaning that its light becomes slightly redder as a result of the light waves being stretched out. This is much like the Doppler Effect we hear when an ambulance speeds by: as the ambulance recedes from us, the pitch of the siren is appreciably lower to our ears than when it was coming towards us, as the sound waves stretch out behind the vehicle. By looking at the redshift of distant galaxies, astronomers could see that almost all the other galaxies were rushing away from us (this is not to imply that we are at the center of the universe... observers in every galaxy would see essentially the same thing). From this discovery, the theory of the Big Bang was born.

Then the next big question: will the universe expand forever, or will it come to a halt and start collapsing, resulting in a Big Crunch? The answer to this question would hinge on whether there was sufficient matter in the universe to pull it all back together. In either case, this means the universe would eventually die -- either from becoming so diffuse that matter can no longer condense into stars and galaxies, effectively ending the energy output of the universe and becoming a cold soup of elementary particles -- or by being consumed in one inconceivably violent collapse of everything in the universe... a real day of reckoning. Neither one of these eventualities are very appealing, but we can take some comfort in knowing that they would be many billions of years in the future.

Then in 1998, it was discovered that not only is the universe expanding, but it's actually accelerating! This creates a problem, because if the universe is accelerating you need some sort of mechanism driving it... the initial energy of the Big Bang is not going to be enough. Cosmologists have been puzzling over the problem ever since this discovery, and usually point to a hypothetical form of energy called dark energy as the culprit. This is where it gets complex, so I'll leave the details to Wikipedia. But the idea of a kind of cosmological constant energy source is not new: Einstein actually came up with the idea, but in his case he introduced the variable to counteract gravity and create a static universe (neither expanding nor contracting), an idea he found less unsettling.

That basically brings us up to the present. Cosmologists are still trying to figure out what's driving the accelerated expansion of the universe, which is where Poplawski's new paper comes into play. Cosmologists have long speculated over whether our universe is really just the inside of a black hole, but Poplawski's work, rejecting the notion of a singularity at the heart of a black hole and using the hypothetical rebound force as an analog for the universe's expansion, seems to be a novel approach to the idea.

The Sounds of Pulsars

2010-07-23T13:41:00.010-04:00

Here's a little treat for the weekend -- take a listen to the sounds of the pulsars!

Of course, these stars aren't really emitting sound, but rather high energy beams of radiation that are detected on Earth by radio telescopes. Radio signals received by these telescopes can be converted into images, but we can also listen to them! (Remember that radio waves are just one of several different kinds of light).

Pulsars are a special brand of neutron star. As the leftover cores of supernovae, they are extremely dense and small, and rotate at incredible speeds, spitting out energetic beams of radiation along their magnetic poles. When one of these beams passes by the Earth, we see it as a flash, like a lighthouse (in fact, when the first pulsar was discovered, some astronomers thought it might be a sort of cosmic lighthouse, left behind by extraterrestrials). So when we listen to the signal of a pulsar, we hear lots of pulses at regular intervals.

Just how fast are the pulsars spinning? Well, it varies. But check out this website and you can hear how fast! Compare this pulsar, spinning about 1.4 times a second, with this one (the Crab Pulsar), spinning about 30 times a second, and this pulsar, spinning about 642 times a second! (Make sure your volume is not too high, because that's one energetic pulsar).

It's one thing to look at a number and be amazed (that third pulsar has a rotational period of 0.00155780644887275 seconds ... what precision!), but I think listening to it spin makes it more real, in a way. Just imagine this neutron star, 10 or 15 kilometers across, spinning 642 times a second! It's enough to make your head spin.

A Comic Rebuttal of the Moon Landing Conspiracy Theories

2010-07-23T09:55:00.008-04:00

Darryl Cunningham brings us this clever rebuttal of the Moon landing conspiracy theories, in comic form:

But as he says, and I've said before, there's really not much you can do to persuade the hardcore conspiracy theorists. And that's the most irritating part -- we feel compelled to confront them with the truth, but it's rarely worth spending the energy, and the hour. After all, what difference does it really make if some guy wants to believe we didn't land on the Moon? It's his loss for missing out on the majesty of reality.

One major exception to this, of course, is climate change. There is a difference between finding fault with scientific findings (which is called scientific debate), and getting your facts from the pundit on Fox News who questions global warming because it's cold outside today. Unlike the Moon landing conspiracies, this sort of thinking-with-your-gut is pervasive, and is a genuine threat to the planet. These views should not be suppressed, of course, but they should be emphatically debunked, because while the Moon landing conspiracy theorists make up little more than a fringe group, usually written off by most serious people, climate change skeptics can and do influence public policy, and set us back in our efforts to reverse global warming. And in the meantime, global temperatures continue to tick upwards, and in the course of a year the United States dumps another 6 billion metric tons of carbon dioxide into the atmosphere.

The Science of Inception

2010-07-21T13:58:00.006-04:00

CultureLab takes a look at the science of Christopher Nolan's hit film Inception.

If you haven't already, you've got to check out this movie while it's still in theaters. It's a new classic, and I can't wait to go see it again.

The Rundown - July 21, 2010

2010-07-21T11:57:00.012-04:00

Lots to cover, not enough time to comment on it all. Here's the rundown:

The House Committee on Science and Technology is complicating the compromise on the future of NASA. PopSci provides more details.
The Messenger spacecraft is discovering that Mercury is an interesting place.
The Mars Odyssey Orbiter has gone into standby mode. JPL is working on the problem.
Cassini has revealed perturbations in Saturn's rings resulting from the gravitational pull of its moons.
The New York Times offers this piece on natural selection in humans.
Russia is building a new commercial spaceport to the tune of $800 million.
the WISE telescope has completed its first survey of the sky, observing over 100,000 asteroids and returning some fantastic photos.
A man in Bosnia believes he's being attacked by aliens after his house has been hit with meteorites six times in the past three years. I'd say it sounds like someone is pulling his leg, but that's an expensive prank!

Happy Moon Day!

2010-07-20T16:06:00.010-04:00

41 years ago today, Neil Armstrong and Buzz Aldrin became the first human beings to set foot on another world. They are two of only 12 men to have ever walked on the surface of the Moon.

The Moon landing is arguably the crowning achievement of life on Earth. Other events may have been more influential for humanity -- domestication of plants and animals, the invention of writing, the advent of modern medicine, or the harnessing of electricity come to mind -- but the journey of men to another world represents a new era for life on Earth: the first time in our history when we Earthlings are able to leave our delicate cradle and discover our place in the vast unknown universe. Forever after, ours will be a space-faring civilization, and if we survive long enough, it seems likely that we will move on to other worlds, perhaps terraforming neighboring planets, establishing permanent colonies beyond the Earth and one day, we hope, venturing to the stars.

For billions of years, life was restricted to the surface of the Earth. A few winged creatures could climb a bit higher, but nothing could push beyond the thin atmosphere that protects us from the cold vacuum of space. Most of our ancestors lived and died without more than a dim notion of anything beyond our planet. But finally, after billions of years of evolution, a curious and determined species emerged, and set about the business of conquering nature's barriers.

After thousands of human generations we, the lucky children of the 20th century, are the first pioneers in space. We see a little farther only because we stand on the shoulders of giants, but for this reason, we owe it to our ancestors and descendants alike to push deeper into the unknown. Nothing less than the survival of humanity may be at stake. But if nothing else, it seems to be our destiny to explore, and to join the community of civilizations that may be humming and zipping about the galaxy. These are just the first few steps of the marathon, but what a marvelous achievement to have gotten this far.

Happy Moon Day.

Southern Hemisphere Moon!

2010-07-15T22:28:00.019-04:00

My buddy just returned from South Africa, where he caught a few games at the World Cup. The assignment I gave him was to take a picture of the Moon, so he sent me the photograph you see above.

What's so special about a picture of the Moon from the Southern Hemisphere, you say? Well, the Moon is UPSIDE DOWN. Of course I mean that it appears upside down to those of us living in the Northern Hemisphere -- please forgive the hemispherical chauvinism.

Not only does water spin in opposite directions going down the drain (experimentally proven by my friend), but we really do see the Moon differently depending on our hemisphere. That's because we're standing on opposite sides of the Earth.

It took me a while to convince my mom, and I had to use my hands to demonstrate it. So I figured I'd just make an illustration. Here it is:

As you can see, the guy in North America sees the North Pole of the Moon as up from his perspective. The man standing in the middle of the South Atlantic sees the South Pole of the Moon as up. Strange consequences of living on a spheroid world.

Gotta love the Moon.

Compromise Reached on the Future of NASA

2010-07-15T16:20:00.009-04:00

Politico is reporting that the Senate Committee on Commerce, Science and Transportation has reached a compromise on the future of NASA. The bill will now go to the full senate for a vote.

As usual, Politico has buried the policy specifics on the second page... you've got to wade through the political commentary to get to it. But it looks like the key changes are "a more regimented, benchmark-based track" for private sector participation in human spaceflight, and "development of a long-range vehicle [beginning] far sooner than the 2015 date the White House specified." Constellation is still on the chopping block, but the Orion capsule will be retained, presumably as the lifeboat for the space station as the White House proposed. NASA funding will be increased by $6 billion, but it's unclear over how many years that's spread. No mention of whether President Obama's goal of sending astronauts to an asteroid is still in the works.

Overall, this sounds like a good compromise, and the White House is praising it. So let's hope that this controversy is just about finished, so we can get on with it!

Voyager 1 - 12,000 Days and Counting

2010-07-14T16:50:00.017-04:00

Last month we told you Voyager 2 marked its 12,000th day in space... almost 33 years. Well, yesterday Voyager 1 hit the same milestone -- an astonishing 12,000 days since it blasted off on its remarkable journey.

Voyager 1 is the most distant man-made object in space, currently about 11 billion miles from the Sun. And it's still talking to us! Its signal, traveling at the speed of light, takes around 16 hours to reach us here on Earth.

In 1990, with its primary objectives completed, Voyager 1 turned its camera around and took one last picture of the Earth. This famous image, above, is known as the Pale Blue Dot (Carl Sagan's book of the same name is a fantastic read).

You've got to check out this video. It gets me every time:

bummer.

2010-07-14T16:36:00.007-04:00

So Fermilab says news of finding the Higgs boson at their facilities was just a rumor. Bummer.

Ah well, we told you it was only a rumor! And anyway, how often do you get to spread a rumor about particle physics?

JAXA Confirms Solar Sail is Working!

2010-07-13T15:28:00.011-04:00

the Japanese Aerospace Exploration Agency (JAXA) has confirmed that the solar sail spacecraft IKAROS is indeed being accelerated by photons emitted from the Sun, which means the solar sail really works!

The spacecraft is showing an acceleration from the solar wind pressure on the order of 1.12 milli-Newtons, which was the predicted value (a Newton is a unit of force, representing the amount of net force required to accelerate a mass of one kilogram at a rate of one meter per second per second). So, the Sun is exerting a force on IKAROS of just over one-thousandth of a Newton every second.

That sounds like very little, and it is. But remember that we're not talking about speed, we're talking about acceleration. So even though this will get the craft off to a very slow start, with every passing second the craft will be going a little faster, and after a while it will have picked up considerable speed.

Read more about IKAROS here.

Juno Gears Up For Jovian Radiation

2010-07-13T14:55:00.006-04:00

The spacecraft Juno, which will blast off for Jupiter in August of next year, has just gotten a slick new Titanium suit.

Juno needs the Titanium armor because Jupiter has an enormously powerful radiation belt that will fry most anything that comes along. Previous missions to Jupiter have had to be careful to avoid the radiation belt so as not to destroy sensitive onboard equipment, but as Juno's mission is partly designed to learn more about the magnetosphere, the radiation will be unavoidable.

Juno is part of the New Frontiers program, a series of medium-cost science missions. The New Horizons spacecraft, which will rendezvous with Pluto in 2015, is the first New Frontiers mission.

Is Gravity Just an Illusion?

2010-07-13T11:03:00.037-04:00

Check out this New York Times article on a debate over the nature of gravity. It's pretty wild stuff.

What's this all about, anyway? Why does it matter how we think about gravity? We understand it perfectly well in our everyday experience, whether we're talking about an apple falling from a tree or a spacecraft going to Saturn. Newton's way of thinking about it was ultimately replaced by Einstein's way of thinking about it, but what difference does it make to us whether we think of gravity as a distortion of spacetime? That doesn't change the way I fall down and scrape my knee.

But scientists are in pursuit of a theory of everything -- one unifying theory that will combine all the known forces (electromagnetic, weak, strong and gravitational) into one super theory. The problem is, our understanding of the very small (quantum mechanics) and the very large (general relativity) are pretty good on their own, but they're a devil to combine. This is where all that weird stuff like string theory and 26 dimensions comes into play. Most of us just glaze over.

But we've already been thinking about these things in "weird" ways. Curvature of spacetime is a good example, because while it is wholly outside of our experience, it's easy enough to grasp. We can visualize stars or planets as sitting on the fabric of space, making indentations that would perturb objects as they come near, like this:

If you imagine a smaller body swooping in within the distortion of the space fabric, its straight path is going to be curved. If it's traveling fast enough, its trajectory will be changed but it will keep flying away, escaping the pull of Earth's mass; but if it's slower, it might be captured by the Earth, spiraling in to impact or becoming a satellite. That's precisely the behavior we observe. But of course, the fabric of space isn't just some giant, invisible trampoline on which everything sits.

In the illustration, we're imagining the fabric of space as a two-dimensional plane, curved or distorted by mass into a third physical dimension (the greater the mass, the greater the distortion). But the universe we experience is obviously 3-dimensional. So by analogy, if we think of our 3-dimensional universe as flat, we can imagine it as curved into a fourth dimension. We can't experience spacetime distortion directly, because we can only experience the world in three dimensions. But we can certainly see the side effects of spacetime distortion, and deduce it (gravitational lensing is another fabulous phenomenon that we can see as result of this strange state of affairs).

Watch Carl Sagan's far more elegant explanation of the fourth dimension here and here.

So when we think about gravity in this way, we can start to understand that all this talk of higher dimensions and wiggling strings is not that much more bizarre, it's really just the next step. Theoretical physics continues to get stranger, but we already know that the universe is a strange place. For instance, we know that time actually slows down on board satellites hurtling around the Earth (as predicted by Einstein), and we've seen peculiar phenomena on the sub-atomic level.

In any case, maybe our way of thinking about gravity is fundamentally flawed in some way. Something's got to give if we're to unify gravity with the electronuclear forces. If we do have it wrong in some way, it won't make any difference in how you fall down and scrape your knee, or visit our neighbors in the solar system. But just as our understanding of quantum mechanics has changed the world forever (think nuclear reactors... and unfortunately, fusion and fission bombs), understanding these forces on a deeper level, as different iterations of the same super theory, could have an enormous impact on our world, and our understanding of the cosmos. And it just might lead to some dazzling breakthroughs, whether it's energy production, interstellar travel, or some other yet-unforeseen technology.

And in the meantime, it's a fun mindbender.

Has Fermilab Found the Higgs Boson?

2010-07-12T16:01:00.013-04:00

The rumors are flying after a blog post suggested the Tevatron at Fermilab may have found the elusive Higgs boson.

I'm a bit out of my element when it comes to particle physics, but the Higgs boson is kind of a big deal. According to the standard model of particle physics, the Higgs boson would be the elementary particle that imbues other particles with mass, but so far no one has been able to detect it. It has been hoped that the Large Hadron Collider at CERN would be able to produce the Higgs... but maybe Fermilab has beaten them to the punch!

Check out this funny and somewhat trippy little New York Times article from a while back, in which a couple of scientists suggest that the Higgs boson "might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather." Woah.

Stay tuned for developments.

Rosetta's Stone Flyby

2010-07-12T15:21:00.015-04:00

This weekend, the European Space Agency's Rosetta spacecraft flew by the asteroid 21 Lutetia and got some great photographs. Take a look at them here.

21 Lutetia is just a pit stop for Rosetta (except that it didn't stop, of course... it whizzed by at over 33,500 miles per hour). The spacecraft is now making its way to rendezvous with the comet 67P/Churyumov-Gerasimenko, where it will arrive in 2014. Rosetta will orbit the comet and drop a landing craft, named Philae, to touch down on the surface. If successful, this will be the first mission to land a craft on a comet.

Below, an image of 21 Lutetia captured on July 10th. Saturn can be seen in the background.

Courtesy of wikipedia:

Churyumov-Gerasimenko has a rather interesting orbital history. Comets are regularly nudged from one orbit to another when they encounter Jupiter or Saturn in close proximity. For this comet it was calculated, that before the year 1840 it was completely unobservable due to its perihelion distance of about 4.0 AU. At this time Jupiter shifted that distance to about 3.0 AU. Later on, in the year 1959, another encounter with Jupiter pushed it to about 1.28 AU, where it is now.

Raw data!

Senate Panel Works to Block Obama's Human Spaceflight Proposal

2010-07-09T09:41:00.019-04:00

The Senate Committee on Commerce, Science and Transportation is working on a bill to block much of President Obama's proposed plan for the future of human spaceflight at NASA. The bill is expected to restore the Orion capsule to its original specifications, authorize the construction of a heavy-lift rocket starting immediately, and will call for one additional shuttle flight, to be flown in the middle of next year. The panel hopes to garner bipartisan support for the bill (as there has been some bipartisan opposition to the President's plan).

I've been somewhat ambivalent about the administration's vision for human spaceflight, so I'm not terribly troubled by any of the developments we've seen on this front. But the most striking feature of the President's plan, to me, has been the emphasis on bringing down costs. Integrating the private sector into orbital missions may be an important step toward greater commercial participation in human spaceflight, but at its heart I think it's mainly about saving money. There's a certain accountability in commercial endeavors that is sometimes unfortunately absent in government projects, so if this route managed to reduce the enormous cost of sending astronauts into space, that would be a boon for the space program as a whole.

Incidentally, I would be all in favor of the senate's plan if they can give the program the money it really needs. In 2005, President Bush set the goal of returning astronauts to the Moon, but the additional funding that Constellation needed was never made available. When President Obama took over, the advisory panel he assembled found that the program was dreadfully underfunded and would never reach its goals in time (a return to the Moon was not realistic until at least 2025, they said). He could either fight for the additional billions of dollars, or revise the program's objectives (he's actually doing a little bit of both).

While I think the President's proposal is a novel one, I understand the apprehension, and there are certainly drawbacks. But if Congress wants to derail his plans, they better think seriously about ponying up to make sure Constellation gets off the ground on schedule. The status quo is just not acceptable.

More Vindication for the "Climategate" Scientists

2010-07-07T11:17:00.021-04:00

A British panel has just found that the so-called "climategate" scientists are not guilty of scientific misconduct. This is the fifth review to have reached the same conclusion.

Climate change skeptics, though, will not be deterred. As has always been the case with conspiracy theorists, they are happy to ignore the abundance of evidence that refutes their beliefs and focus instead on a few instances of fuzzy numbers, clumsy statements and less-than-perfect science. All it takes is a few embarrassing e-mails, taken out of context, for them to claim that the whole global warming house of cards is falling.

Even so, this controversy is a good reminder that scientific inquiry must be an open and honest process, so as to minimize these sorts of incidents which needlessly set back the cause of saving the planet. Dishonesty in any scientific endeavor undermines legitimate science, and is almost always counterproductive to the cause it is meant to serve.

In any case, there is a sort of selective blindness on the part of climate change deniers. They are eager, for instance, to hold up the powerful winter blizzards as evidence that global warming doesn't exist, but where are they during the summer heat waves, like the one sweeping through the East Coast right now? Sean Hannity is curiously silent on this front during the summer months.

We know that these trends -- hotter summers, and yes, bigger storms in the winter -- are indeed a predicted result of climate change. But we cannot hold the weather of any single day, in a single location, as proof or disproof of climate change. We must be careful not to point to these high temperatures alone as evidence of global warming, lest we make the same flawed interpretation. Anecdotal evidence is just not good enough. Rather, we must rely on global data, collected over many years; and luckily, the data is on our side.

Photo Credit: Mike Clarke.

Hopeful Signs for Hayabusa

2010-07-07T10:28:00.003-04:00

JAXA has just released this image, which may be a particle of dust captured from the asteroid 25143 Itokawa. If that's true, that means Hayabusa has not returned to Earth empty-handed. But this could turn out to be the most valuable (or expensive) space dust ever collected.

This may seem like a pitiful return on the investment, especially if you compare it to the hundreds of pounds of moon rocks returned by the Apollo astronauts. But the Stardust spacecraft also came back to Earth with little more than microscopic particles from Wild 5's coma, so this is not a wholly disappointing sampling (indeed, in light of Hayabusa's troubles, JAXA will be relieved to find anything inside). So long as there's enough material available to study, this will be deemed a success.

Thoughts On July 4th

2010-07-02T13:41:00.005-04:00

Well, July 4th is this weekend, which means it's time to celebrate America! Of course, we'll always remember the courage of our forefathers, and the sacrifices of the brave men and women in uniform. But the fourth of July is also an opportunity to reflect on all of the great endeavors of our young nation.

And in this vein, let us not forget our astonishing exploits in space! Only 55 years after the first powered flight by the Wright Brothers, we sent our first satellite into space. And just eleven years after that, man first set foot on another world. What a spectacular achievement! For millennia, human beings were restricted to the ground, and in the course of just 66 years, we went from managing only a few seconds aloft to making quarter-million mile journeys in space.

Since that time, we have completed a preliminary reconnaissance of the solar system, and whole worlds have been revealed to us for the first time in history. The wonders of the solar system, from the mysterious moons of Jupiter and Saturn to the eerie blue clouds of Neptune, were little more than points of light in the sky until our robotic spacecraft ambassadors sent us the first breathtaking close-up images. We've sent vehicles to explore the vast barren landscape of Mars, and we've landed a probe on Saturn's giant moon Titan where, perhaps, there may be stirrings of extraterrestrial life. And yet, there is still much to do! In just five years, we will receive our first close-up images of the massive, spherical asteroid Ceres, as well as the first photographs of the surface of Pluto! Like Titan, the icy Jovian moon Europa, with its massive ocean of liquid water, calls to us for exploration. And of course, we ache to learn more about our remote, titanic neighbors in the outer solar system, and the utterly unknown Kuiper Belt beyond.

Meanwhile, space telescopes have revealed the fabulous beauty of the galaxies in stunning detail, and have shown us the first planets around neighboring suns in the Milky Way. We are beginning to know the vast universe that is our home, and our place within it. And more locally, communications satellites have revolutionized our lives and have, in a very real sense, transformed us into a global community. And in so doing, our national chauvinisms are starting to trickle away.

I've much more to write on the subject, but I'm off to vacation with my family. I hope everyone has a safe and lovely holiday weekend. We'll see you back here next week.

Did Hayabusa Come Back Empty-Handed?

2010-07-02T11:46:00.004-04:00

The New York Times chronicles the troubled journey of the Japanese space probe Hayabusa, and the uncertainty of Japan's future in space technology. And as of right now, we still don't know if any asteroid samples were retrieved.

As we've mentioned previously, the projectile mechanism that was supposed to dislodge samples from the asteroid malfunctioned, so JAXA has known for years that there was a chance the probe would return empty-handed. But we won't know for some time whether anything of value was collected; as you can imagine, the scientists are taking extreme care not to contaminate anything inside.

Regardless of whether the asteroid samples are within, Hayabusa's return itself is a triumph. With three of four engines failed, it's remarkable that they were able to get it back to Earth at all. So even as JAXA's technology may have come up short this time around, it's still a win in my book; after all, it's still the only spacecraft to have ever landed on an asteroid and returned to Earth.

New Exoplanet Image - First from the Ground

2010-07-01T14:28:00.011-04:00

Check out this image from 2008, recently confirmed to be a photograph of a planet around another star:

There have been some conflicting reports about this, as Bad Astronomy explains. I've seen it touted elsewhere as the first direct image of an exoplanet, but that's not the case. Rather, it is the first direct photograph of an exoplanet taken by a telescope on the ground.

Ground-based telescopes have traditionally been less well-suited for this type of work than space telescopes, as poor seeing creates distortions that blur out such faint objects. But as we mentioned a few days ago, adaptive optics are now starting to close the gap.

The planet, about 470 light-years away, is roughly 8 times the mass of Jupiter and orbits some 330 Astronomical Units (AU) from its star. That's more than 30 billion miles! By comparison, Pluto's average distance from our Sun is only about 39 AU.

Moonbase Alpha Game - Coming July 6th

2010-06-29T14:16:00.005-04:00

On July 6th, NASA is unveiling Moonbase Alpha, a brand-new (and presumably free) multi-player video game. Looks awesome!

Check out the trailer:

Voyager 2 - 12,000 days and counting

2010-06-29T11:37:00.011-04:00

Yesterday, Voyager 2 hit an incredible milestone: 12,000 days of continuous operation (Voyager 2 will celebrate its 33rd birthday -- er, launchday -- on August 20th).

Voyager 2 is currently about 9 billion miles from the Sun... or about 12.8 light-hours. That makes it the second most distant man-made object ever... eclipsed only by its twin spacecraft, Voyager 1, currently about 11 billion miles from the Sun.

Fighting the Space Junk

2010-06-29T10:38:00.016-04:00

Here's some good news: President Obama's new space policies include a new emphasis on cleaning up space junk.

As we pointed out a while back, it's starting to get crowded up there. After 50 years in space, we've left quite a horde of decommissioned satellites, jettisoned modules and miscellaneous debris floating in orbit (and you might recall China's decision to blow up a satellite back in 2007, turning one big piece of space junk into thousands of tiny pieces of space junk). And even though space is still very empty (the diagram above is obviously not to scale), the presence of this garbage is still a major hazard. It's especially difficult to track the small pieces, and you never know when something might come careening toward the International Space Station, for instance -- puncturing some vital piece of equipment, or perhaps the spacesuit of an unlucky astronaut on a spacewalk. Satellites, of course, are equally vulnerable to interference from space debris.

So let's hope they can work it out. Clean-up will be a tall order, but prevention is a good first step.

Check out another illustration of the space junk problem here.

Invading Carp Threatens the Great Lakes

2010-06-24T09:18:00.008-04:00

The New York Times reports that the non-native Asian Carp have made it past a protective barrier and could be on their way to invading the Great Lakes.

When organisms are introduced into a new habitat where they have no natural predators, they can do serious damage -- the population can grow uncontrollably and they can push out native species. Kudzu, which was introduced to the United States from Japan in 1876, is now considered a pest weed, growing out of control throughout the Southeast and expanding every year. And in Hawaii, where nights used to be quiet, an infestation of non-native tree frogs is filling the forests with a maddening noise (and since there are no natural predators for the frogs, there are a lot more voices in the chorus).

So what's the big deal if Asian Carp get into the Great Lakes? Well, not only would they interrupt the natural balance of the food chain, and threaten other species... they also have a very curious habit, one that looks like it might be a little bit of a nuisance:

Check out this CBS report on the invasion.

The Music Scene

2010-06-23T17:00:00.004-04:00

It's a little off-topic, but this video is sublime:

"The Music Scene" from Anthony Francisco Schepperd on Vimeo.

The song is "The Music Scene" from the album of the same name by Blockhead.

The Webb Telescope's Future Home

2010-06-23T15:16:00.006-04:00

Physorg explains why L2, the second Lagrangian Point, is a great place to park the James Webb Space Telescope.

The Webb Telescope will be launched in the summer of 2014 and will be positioned about 1.5 million kilometers from the Earth, far beyond the orbit of the Moon. This means that, unlike the Hubble Telescope, it will never be serviceable in space. So we better get it right while it's still on the ground!

ISS Crew Photographs Aurora Australis

2010-06-22T09:22:00.007-04:00

Check out this photo of the aurora australis (southern lights), taken in late May by the Expedition 23 crew on board the International Space Station. According to NASA, this event was most likely caused by a coronal mass ejection from the Sun on May 24th.

Read more about it here.

Happy Summer Solstice!

2010-06-21T10:45:00.009-04:00

Today is the Northern Hemisphere's Summer Solstice, which means it's the longest day of the year. Woohoo!

In celebration of the solstice, take a look at this great little clip from Carl Sagan's Cosmos, which describes the Greek mathematician Eratosthenes' calculation of the circumference of the Earth some 2,200 years ago. The summer solstice played a key role in Eratosthenes' discovery:

Homemade Weather Balloon Photographs Earth from 24 Miles High!

2010-06-21T01:18:00.013-04:00

Check out this incredible video from cinematographer Colin Rich:

Pacific Star II from Colin Rich on Vimeo.

This is right around the altitude where Felix Baumgarter will jump for his supersonic freefall later this summer.

Weekend Fun - Galaxy Crash!

2010-06-18T15:23:00.010-04:00

Since there probably won't be any updates over the weekend, I thought I'd leave you with this little gem: GALAXY CRASH!

Just click on "Applet" on the left side of the page to open up a new window and start simulating your own galactic collisions. You can adjust the galaxies' relative orientation, their mass differential, the number of stars, etc. And you can drag your mouse on the screen to look at the collision from any angle!

Galaxies occasionally collide -- in fact, astronomers predict that our own Milky Way galaxy will collide with our neighbor, The Andromeda Galaxy (M31), some 3 billion years from now. But because the distances between the stars in each galaxy are so vast, the chances of star systems actually crashing into each other are much smaller than you might think.

Check out this animation of galaxies colliding (around the 6 minute mark), from Carl Sagan's COSMOS:

Congress Turns Up the Heat on NASA

2010-06-18T14:45:00.002-04:00

It's getting heated up on the hill.

NASA missed a deadline to provide Congress with an updated budget (containing additional details relating to President Obama's plan for the future of manned spaceflight), so now the oversight panel is insisting that NASA administrator Charles Bolden produce "all materials NASA relied upon in formulating its proposal." Yikes.

Meanwhile, the engineers building the Orion capsule are still in limbo, not knowing whether they'll be building the craft to original specifications, or a stripped-down model for use as a lifeboat from the space station. And of course there's always the possibility that the capsule could be scrapped altogether.

As I've said before, the Obama plan could be a good idea. But right now, no one has enough information to make that call. And irritating Congress is not a great way to get your plan approved.

Tour of the Mars500 "Spacecraft"

2010-06-18T14:05:00.005-04:00

Diego Urbina, Italian crew member of the Mars500 project, gives us a brief tour of the facilities:

Diego and his crew mates are locked up in this mock spacecraft for 520 days. The project will study the effects of long-term isolation on astronauts on a voyage to Mars.

New HBO Documentary - GASLAND

2010-06-18T09:12:00.018-04:00

I caught director Josh Fox on Morning Joe this morning promoting his new HBO documentary, GASLAND -- a look at the environmentally unsound method of natural gas extraction known as hydraulic fracturing. The film will premiere on HBO Monday night, June 21st at 9PM. Take a look at the trailer (or read the synopsis):

Trailer

Natural gas has been billed by its advocates as the cleaner, safer alternative to oil. But just like BP's uplifting "Beyond Petroleum" commercials (which irritated me even before the Gulf Oil Spill), it seems that the unsafe practices are once again hidden behind a thin varnish of trendy spokespeople, hip visuals and breezy music:

Increasing natural gas production as a means to going green has always seemed to me like a stop-gap measure anyway... what is the point of restructuring our energy economy to transition to another fossil fuel? Even if it is more abundant and somewhat cleaner than oil, it just doesn't make much sense to me, because fossil fuel resources are inherently finite, which means eventually we will have to make another change. It's understandable that people are anxious about making big changes in our energy economy, but to me it's sort of like taking off a band-aid: it hurts less if you do it all at once.

IKAROS video

2010-06-17T21:55:00.004-04:00

For those of you who want a better sense of the IKAROS Solar Sail spacecraft, check out this excellent video from JAXA (unfortunately, no subtitles):

A Boon for Ground-Based Optical Telescopes

2010-06-17T10:50:00.022-04:00

Ground-based optical telescopes have special problem: atmospheric turbulence distorts images.

Historically, the solution to this problem has been to take the telescope above the turbulence. At first this meant building telescopes high up on mountains, where seeing is better. And when the technology became available, we also put telescopes in space.

But now, adaptive optics are making it easier to make clear observations from the ground. The Large Binocular Telescope (LBT) in Arizona has just installed a brand new system, which is expected to yield images up to 10 times sharper than the Hubble Space Telescope.

That's great news, because it's very difficult, and sometimes impossible, to update hardware on a space telescope (there will be no more repair missions to Hubble, and the James Webb Telescope, which will be situated at the second Lagrangian point approximately 1.5 million kilometers from Earth, will never be serviceable in space). And of course, you can build much larger telescopes when they don't have to be taken up into space on a rocket.

I can't wait to see these new images!

At right, the Large Binocular Telescope on Mount Graham in Arizona.

Living in the Future, part 5 - Watson's Jeopardy! Debut

2010-06-17T10:23:00.011-04:00

Scientists at IBM have developed Watson, a computer capable of interpreting questions in "natural language" ... complete with context clues and the nuances of everyday speech. Watson will get a chance to compete on Jeopardy! sometime as early as Fall. But "he" is already tearing up the competition in practice rounds.

Check out this great Times Magazine article, or compete against Watson here!

IKAROS Solar Sail is Deployed!

2010-06-16T09:33:00.012-04:00

A small separation camera has detached from IKAROS and has taken a picture of the entire craft with sail unfurled. Check it out:

Read the JAXA press release here.

Unlike Earth-bound vehicles, spacecraft don't have to keep their engines going to keep moving. And since propellant is very expensive to lift into space, engineers work out clever ways to economize, so they can do a lot with a little (check out this great article on extending the Cassini mission). Conventional rockets get a lot of acceleration all at once, but as soon as the engine is turned off, they just cruise through space at a constant rate, more or less.

The solar sail is sort of like the tortoise racing the hare. It starts off very slow, with the photons bouncing off the sail and creating a small amount of thrust. But that thrust is constant, so over time the craft continues to accelerate. It can pick up incredible speed and, if it is demonstrated to be successful, could significantly reduce the time it takes to reach neighboring worlds. And for farther destinations, the craft could reach higher speeds.

I'd love to see this technology catch on. So let's hope IKAROS has got the right stuff.