In a newly published paper, John Rummel from the SETI Institute and Gerhard Kminek from the European Space Agency suggest that it is time to start preparing in earnest for a Mars Sample Return mission, and to come up with a new protocol for testing any materials brought back to Earth. This is a very timely idea, as such an effort could get under way as early as two years from now, with the launch of NASA’s Mars 2020 mission to start collecting samples.
The existing draft protocol, which calls for returned samples to be analyzed in a bio-containment facility, is 16 years old, and needs to be updated based on new scientific insights. The first samples from Mars could reach Earth as early as 2029.
Planning for a Mars sample receiving facility was supposed to start this year. The plans will have to specify the biohazard tests, instrumentation, and procedures to be used in a sample-receiving facility. These could apply to samples returned from Mars or from elsewhere in the Solar System, including Saturn’s moons Enceladus and Titan.
The topic of how to address planetary protection concerns is sure to be hotly debated at the upcoming Second International Mars Sample Return Conference in Berlin. While I recently had a difference of opinion with John Rummel—a former NASA Planetary Protection Officer—regarding possible “forward contamination” (the danger of transferring Earth microbes to Mars), I fully concur with him on the threat of possible backward contamination of our own planet. While the risk of endangering Earth with Martian microbes is likely to be quite low, the consequences for our planet’s biosphere could be devastating. Thus, a sample-receiving facility with containment areas of the highest biosafety level and strict biohazard protocols are essential.
My colleague Alessandro Airo from the Technical University Berlin and I would go another step further. We suggest in our abstract submitted to the conference that any sample to be returned to Earth first be examined in situ on Mars to attempt a determination of whether it contains microbial life. Not only would this make sense for planetary protection purposes, it would give us another early opportunity to detect life on Mars. Once the sample is stored in the return cache, it might sit there for a very long time, including the return flight to Earth, and indigenous Martian life may not be able to survive the trip—particularly if it uses light as an energy source. We should take every opportunity to resolve the question of whether Martian life exists, even before the samples arrive back on Earth.