Thursday, November 25, 2010
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.
Wednesday, November 17, 2010
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.
Tuesday, November 9, 2010
"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:
Tuesday, November 2, 2010
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.