You know what? Maybe we ought to reconsider this whole thing about looking for life on other worlds. It would be nice to find it, of course. But that doesn’t mean we could handle it—biologically, epidemiologically and most important, emotionally.
Mars, which was once awash with water, might once have been fairly churning with life too—and some of it may well linger in spots in which the water endures. As the Space.com piece points out, it is possible that Earthly life and potential Martian life are even related: Meteorites from Mars that struck Earth billions of years ago could well have harbored microorganisms that survived the journey within water-bearing pockets in the rocks, giving rise to life here. If that’s the case, not only have we found Martians, we are Martians. But any relationship between current Earthly and Martian life could increase the risk that Martian microbes find us hospitable hosts.
The odds of finding life on Mars are unknown and unknowable. The odds of being able to scoop it up and bring it back to Earth intact add a further degree of uncertainty. And the risk of a pathogen escaping and a pandemic ensuing, while not impossible, feels far more the stuff of a screenplay than a journal paper.