News: AAAS 2009 Annual Meeting News
http://news.aaas.org//2009/0217alien-life-at-home-and-abroad.shtml
Researchers at AAAS Annual Meeting Describe Search for Alien Life, Both Near and Afar
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Read full coverage of the 2009 Annual Meeting from Science and AAAS.org!
Alan Boss, a staff scientist with the Carnegie Institution for Science, said in a AAAS podcast that, given the billions upon billions of stars in the universe, it's "inevitable that Earth-like planets are out there."
Also inevitable: That story got extensive news media pick-up in the U.S. and overseas.
Here's what Steve Connors, science editor of the U.K.-based Independent, had to say:
"A leading astronomer confidently predicted yesterday that the discovery of an earth-like planet--possibly in the water-friendly 'habitable zone' around a nearby star--would soon be announced, after two satellite studies by the European Space Agency (ESA) and the US National Aeronautics and Space Administration (NASA)."
And he quoted Boss: "Within about three or four years, there will be a press conference at NASA headquarters and they will tell us just how frequently Earth-like planets occur and once we know that we will know how to take the next steps in the search for habitable planets."Boss and his colleagues are looking for new insights from ESA's Corot orbiting telescope, and NASA's Kepler telescope, which is scheduled for launch on 5 March. Ian Sample, writing in the Guardian, noted that quoted Boss further: "We will be absolutely astonished if Kepler and Corot don't find any Earth-like planets."
An account by the BBC noted that so far, about 300 planets have been discovered beyond our solar system, though few would likely support life. But "based on the limited numbers of planets found so far," the story says, "Boss has estimated that each Sun-like star has on average one 'Earth-like' planet. This simple calculation means there would be huge numbers capable of supporting life."
In an interview with BBC, Boss said: "Not only are they probably habitable but they probably are also
going to be inhabited. But I think that most
likely the nearby 'Earths' are going to be inhabited with things which
are perhaps more common to what Earth was like three or four billion
years ago." Which means simple bacterial life forms.
At another Annual Meeting symposium, however, other researchers suggested looking for "weird life" closer to home.
"No need to leave the planet to look for
alien life," wrote Irene Klotz of the Discovery Channel. "Perhaps it's here,
in peaceful coexistence with or complete isolation from the standard
variety that permeates Earth."
Added Wired blogger Alexis Madrigal: "They might not be green or spit out cute catchphrases."
Paul Davies, an astrobiologist at Arizona State University, was a speaker at the symposium,a nd Madrigal quotes him, and he noted that such life might be a remnant of an ealier "biogenisis" on earth, a flowering of life that preceded our own. "If life did happen many times," he says in Madrigal's story, "there could be something like a shadow biosphere that either was, or is, all around us.It's entirely possible that some fraction of microbial life could turn out to be alien or 'weird' life as we prefer to call it."
Such life might be distinguished by its reliance on "different
chemical processes than we've ever seen before," wrote Madrigal. For
example, it might use arsenic as all known living things use
phosphorous.
"Scientists already have some candidates for alien Earth life,"
wrote Klotz, whose story appeared on MSNBC.com. Among them: "a
population of arsenic-fed microbes living in a California lake and a
colony of strange organisms near deep-sea vents."
When researchers looked at hydrothermal vents in the ocean, Madrigal wrote, they "found sulphur-eating microbes thriving in the absence of sunlight. But those creatures already have a spot on the tree of life and, if you go far enough back, share a common ancestor with all other life that we know on Earth.
"Truly 'weird' life would have to be much weirder. It would function using different elements or have different basic genetic material. Stumbling upon this life could be quite difficult, as the likeliest spot for one of these life forms would appear to be one of the thousands of unexplored deep sea vents."All rights reserved. Read our privacy policy and terms of use. Contact info.
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