Monday, August 30, 2010

Asteroid Discoveries, 1980 - 2010

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.

Tuesday, August 24, 2010

Intelligent Machines and the Search For Extraterrestrial Life



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.

Wednesday, August 18, 2010

Richard Hoagland, Pseudoscience and the 2012 Doomsday Prophecies

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.

Monday, August 16, 2010

Back From Holiday!

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.

Friday, August 6, 2010

Vacation!

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!

Tuesday, August 3, 2010

Citizen Scientists Analyze Stardust Data


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."

Monday, August 2, 2010

The Rundown - August 2nd, 2010

  • 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.