Update on 8 November: The rocket carrying the Phobos-Grunt spacecraft launched at 2016 GMT but
A ragtag group of rugged travellers is sent on a three-year round trip to a desolate moon that might be the site of a future human outpost in space.
No, that鈥檚 not a pitch for a reality show 鈥� it鈥檚 a description of an experiment called (Living Interplanetary Flight Experiment) that is scheduled to set off for the larger of Mars鈥檚 two moons, Phobos, on 8 November, from Baikonur, Kazakhstan.
Advertisement
The travellers are not celebrities, but some of Earth鈥檚 toughest organisms, including the bacterium Deinococcus radiodurans and water bears 鈥� tiny invertebrates that can survive extreme temperatures and the vacuum of space in low-Earth orbit.
The brainchild of the non-profit Planetary Society of Pasadena, California, LIFE will pack inside a container the size of a hockey puck and then hitch a ride aboard Russia鈥檚 Phobos-Grunt (Phobos-Soil) spacecraft.
LIFE will test an idea called transpermia, in which organisms 鈥渃ould be ejected off one planet in impacts, travel through space inside rocks, then be deposited on another world鈥�, says Bruce Betts, LIFE鈥檚 lead scientist. Phobos-Grunt 鈥渨ill act as a simulated rock carrying life between planets鈥�. 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鈥檚 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 sources. While organisms taken to the moon on Apollo missions went beyond the magnetosphere, it was only for a few days at a time. LIFE should expose its organisms to the radiation and temperatures of space for three years.
Like a reality show, LIFE has stirred up controversy. 鈥淲hat happens if the mission crashes and the microbes are allowed to get loose?鈥� asks , an astrobiologist at the Bay Area Environmental Research Institute in Moffett Field, California. 鈥淭hen you have potentially ruined your chances for looking at the origin of organic material or potentially life forms鈥� on Phobos, he says.
That is essentially true for any missions studying Phobos-Grunt鈥檚 landing site with on-board instruments, says Catharine Conley, NASA鈥檚 officer, who is charged with ensuring that agency projects do not contaminate other solar system bodies with terrestrial life. 鈥淚t would be difficult to convince anyone that detected organics were not released from the spacecraft,鈥� she says.
For missions returning samples back to Earth for more detailed analysis, it may be possible to identify any contamination from the mission. 鈥淚f one measured the isotope ratios, those would have characteristics of Earth organisms,鈥� Conley says.
鈥淚f the organisms survive, it could strengthen the idea that life on Earth came from other planets鈥�
And what of the risk of contaminating Mars? Fortunately, it is extremely slim, says Conley.
To cause contamination, , also in Moffett Field, points out that the LIFE capsule would have to miss Phobos, survive the fiery entry into Mars鈥檚 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鈥檛 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 鈥� the first material to be brought back from a moon other than our own. The samples could help settle a burning question 鈥� are Mars鈥檚 two moons, Phobos and Deimos, captured asteroids, leftover building blocks of Mars, or something else entirely?
The samples may even contain dust from Mars itself that was blasted up during an impact.
