The article starts off with the results to date of the search for extrasolar planets. (We've found more than 150 to date, believe it or not.) It then goes on to talk about the fact that we've yet to come up with any that are remotely like Earth, in terms of a potential biosphere and conditions suitable for supporting human life, or at least of growing their own form of intelligent life. Fortunately, the author points out that most of the early planetary discoveries were made using the "wobble theory" where the presence of an unseen planet is inferred by the "wobble" it gravitationally induces in its star.
In retrospect, it seems only natural that the first planetary systems these astronomers discovered were psychotic beasts unlike anything previously imagined. The more massive a planet is and the more tightly it circles its star, the bigger the wobble and thus the easier it is to detect. As a result, the first planets were so-called "hot Jupiters," orbiting their suns in a matter of days instead of years, lethally searing and dense.To be realistic, however, we also can't allow ourselves to fall into a trap of thinking that you can't swing a dead cat without hitting a star harboring an earthlike planet. There are some minimum requirements you need to meet.
If there's a chance that habitable planets are rare, you could probably have predicted that the Hypnochrists™ would seize on that as support for intelligent design and a new chance to dis Darwin. So did it happen? Oh, you betcha, Sparky.The list of astronomical requirements for life gets longer and more exacting every year: the home star has to be far enough from the galactic center to be away from lethal black hole pyrotechnics, for example, but not so far into the galactic sticks that stellar evolution has not yet produced enough of the heavier elements like oxygen and iron needed for planets and life.
Among other things, its planet has to have liquid water, a magnetic field to keep away cosmic rays, plate tectonics to keep things stirred, a giant outer planet to keep away comets and asteroids and perhaps a big moon to stabilize its rotation axis.
Of the 200 billion or so stars in the galaxy, what fraction have the lucky combo to win this cosmic lottery? Faced with the same paltry data, different astronomers get vastly different conclusions, ranging from hundreds of thousands to one, namely our own.
This would merely be an interesting academic argument except for a film that is going around, and which I recently viewed, called "The Privileged Planet," which suggests that the Earth's nice qualities are no accident.
The film, produced by Illustra Media in California, is based on a book of the same name by Guillermo Gonzalez, an astronomer at Iowa State, and Jay W. Richards, a philosopher and vice president of the Discovery Institute in Seattle.
The "Discovery Institute", eh? Sounds scientific enough. I wonder who they are?
There's the next thing to put on your watch list, progressives. Once the Evangelicals are done ripping Darwin a new rectum they're coming after the Big Bang. This article, however, closes on a comfortingly rationale note, leading to the title of this blog entry. All is not lost. I'll leave you with the closing bits, but recommend you follow the link and read the original. It's a very good piece.It argues that Earth is so special and unlikely that it must be the work of an intelligent designer. "What if it's not a cosmic lottery?" Dr. Richards asks in the film.
The Discovery Institute advocates "intelligent design," a notion that posits the intervention by a designer, whether divine or not, in the origin and history of life, as an alternative to standard evolutionary biology. Illustra Media has produced a series of videos in support of this idea.
The showing of the film at the Smithsonian Museum of Natural History last month exacerbated the worries of many astronomers that the Big Bang would be next on the hit list of creationists.
But the argument from design, many scientists say, is circular. Charles Stevenson, a planetary scientist at Caltech, said that it was no surprise that the Earth appears suited to our needs. "That's what Darwinian evolution tells us should happen. We are adapted to our world," Dr. Stevenson said.
Who knows what powers atoms in their collective and complex majesty have to respond to their environments over time?
Lacking anything approaching a final theory of physics, or of how planetary systems form, and of more than one example of life - the biosphere on Earth - scientists have no way of actually knowing how unlikely various properties of life and the universe are. In science the smart money is always on surprise.
Everybody agrees that intelligent technological life is a much greater leap, but it might be instructive to consider who is laying down bets on at least looking for it. Among the financial angels of the search for extraterrestrial intelligence, or SETI, have been people like Paul Allen, the co-founder of Microsoft; the late Barney Oliver, William Hewlett and David Packard, leaders of Hewlett-Packard; Gordon Moore, the founder of Intel; and the novelist Arthur C. Clarke, who invented the idea of the communications satellite.
The smart money isn't always right, but this is certainly smart money.
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