MARS: COULD MARTIAN ROL SAMPLES CONTAMINATE OUR PLANET WITH MICROBES?

NASA and ESA plan to bring back samples from the Red Planet within the next two decades

- COLIN STUART

NASA and the European Space Agency (ESA) are teaming up to return a sample of Martian material to Earth in the 2030s, but that has provoked fears in some quarters that we could be bringing back more than just rock and air. Could we inadvertently contaminate Earth's biosphere with Martian microbes? The scientific desire for a Mars sample return is clear.

The Moon rocks returned to the Earth by the Apollo astronauts over half a century ago are still studied to this day and are a treasure trove of invaluable information about the Moon's composition, history and formation.

And while we've had a permanent presence on the Martian surface for 25 years now, scientists are keen to study pristine pieces of Mars in the lab. After all, our laboratories on Earth are far more advanced than anything we can squeeze into a rover.

The plan is to dispatch two courier spacecraft to Mars in the late 2020s to collect samples of rocks, soil and atmosphere gathered up by the Perseverance rover currently trawling the Martian surface. A spacecraft would land nearby and transfer the samples over from Perseverance. It would then launch into Mars orbit to rendezvous with the second spacecraft, which would then transport the samples back to Earth sometime in the early 2030s.

But what are the chances they'll bring back more than they bargained for?