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 radiodurans and water bears – 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 10 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 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. "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.
That is essentially true for any missions studying Phobos-Grunt's landing site with on-board instruments, says Catharine Conley, NASA's planetary protection officer, who is charged with ensuring that agency projects do not contaminate other solar system bodies with terrestrial life.
"It would be difficult to convince anyone that detected organics were not released from the spacecraft," she says.
For missions returning samples back to Earth for more detailed analysis, it may be possible to identify any contamination from the mission.
"If one measured the isotope ratios, those would have characteristics of Earth organisms," Conley says.
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