A RAGTAG group of rugged travellers is sent on a three-year round trip to a desolate moon that might he the site of a future human outpost in space. No, that's not a pitch for a reality show - it's a description of an experiment called LIFE (Living Interplanetary Flight Experiment) that is scheduled to set off for the larger of Mars's two moons, Phobos, on 8 November, from Baikonur, Kazakhstan.
The travellers are not celebrities, but some of Earth's toughest organisms, including the bacterium Deinococcus racifodunins and water bears - tiny invertebrates that can survive extreme temperatures and low Earth orbit. The brainchild of the non-profit Planetary Society of Pasadena, California, LIFE will pack to such hardy organisms inside a container the size of a hockey puck and then hitch a ride aboard Russia's Phobos-Grunt (Phobos-Soil) spacecraft.
LIFE will test an idea called transpermia, in which organisms "could be ejected off one planet in impacts, travel through space inside rocks, then be deposited on another world", says Bruce Betts, LIFE's lead scientist.
Phobos-Grunt "will act as a simulated rock carrying life between planets". If the organisms survive, it would strengthen the idea that life on Earth might have come from other planets, or has travelled to other planets. Phobos lies far beyond Earth's protective magnetosphere, so LIFE should provide a glimpse of what happens when organisms are not shielded from many of the damaging charged particles from the sun and other galactic sources.
While organisms taken lo the moon on Apollo missions went beyond the magnetosphere, it wa: only for a few days at a time. LIFE should expose its organisms to the radiation and temperatures of space for three years, Iike a reality show, LIFE has stirred up controversy. "What happens if the mission crashes and the microbes are allowed to get loose?" asks Rocco Mancinelli, an astrobiologist at the Bay Area Environmental Research institute in Moffett Field, California.
"Then you have potentially ruined your chances for looking at the origin of organic material or potentially life forms" on Phobos, he says. And what of Mars? Fortunately, the risk of contaminating the Red Planet is extremely slim, says Catharine Conley, NASA's planetary protection officer, who is charged with ensuring agency projects do not contaminate oche) solar system bodies.
To cause contamination, Pascal Lee of the Mars Institute, also in Molten Field, points out that the LIFE capsule would have to miss Phobos, survive the fiery entry into Mars's atmosphere and open up on the surface. Any organisms still living would have to survive the barrage of ultraviolet solar radiation. In desiccated, inactive states, they would not be able to reproduce.
But LIFE isn't the only interesting thing about Phobos-Grunt. Assuming the spacecraft lands on the moon in February 2013, as planned, it will scoop up about 100 grams of soil to bring back to Earth in August 2014- the first material to be brought back from a moon other than our own. The samples could help to settle a burning question - are Mars's two moons, Phobos and Deimos, captured asteroids, leftover building Hocks of Mars, or something else entirely? The samples may even contain dust from Mars itself that was blasted up during an impact.
SOURCE : NEW SCIENTIST MAGAZINE NOVEMBER 2011
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