Bacteria: the Ideal Astronauts?

In August 1996 David McKay and Everett Gibson from NASA JSC stunned the world by publishing a paper in Science magazine that reported evidence of fossilized microorganisms found within the ALH84001 meteorite that came to Earth from Mars. In the ensuing months and years, interest in life on Mars – and elsewhere – was rekindled.

The notion that rocks could be blasted off of one planet by an asteroid impact and land upon another was not exactly new. But could life be carried within a rock between planets and survive the trip to take root on another world? The trip would not necessarily be all that smooth.

Enter Deinococcus radiodurans. In an article in today’s Science magazine, researchers at The Institute for Genomic Research (TIGR) report that they have determined the entire genetic sequence of this bacterium. D. radiodurans can survive gamma radiation exposures of 1.5 million rads which literally blast its DNA apart. It then reassembles its DNA all by itself with no apparent ill effects. This organism can also be completely dried out and then be revived and can survive doses of ultraviolet radiation that would kill most other forms of life. Sounds like the perfect organisms to send on a long trip inside a rock between planets! Indeed, it is so robust that it is being considered for use in cleaning up radioactive waste dumps.

° Radiation resistance resources from the SpaceRef Directory

° Press release from The Institute for Genomic Research (TIGR)