Scientists want to store Mars samples on Moon: Here's why

Frederick Moxley of the Strategic Threat Analysis and Research (STAR) Laboratories in Idaho and Anthony Ricciardi of McGill University in Canada published their proposal in the journal Ambio, calling for a dedicated extraterrestrial biocontainment facility on the lunar surface.

The key point of their argument is that any facility on Earth cannot ensure complete containment of any alien life form in the event of an accidental spillage, but isolation from Earth that exists on the moon naturally serves as their so-called “quarantine shield".

It means that all samples collected from outer space must be sent to this facility on the moon prior to bringing them back to Earth using robotic means only.”

The author Ricciardi, who specialises in biological invasions, makes a very clear analogy between the alien microbes and invasive species, which is supported by decades of scientific studies.

When organisms end up in the wrong place at the wrong time, the effects are usually catastrophic and can cause irreversible damage, the author says.

According to the scientists' study, strains of the Enterobacter bugandensis bacteria collected from the International Space Station have been shown to evolve into completely different species from those known on earth.

If such organisms were to find their way back to the planet as contaminants in samples, then they may pose a biological threat which was not anticipated before.

This paper highlights a unique threat model referred to as “sequential forward and back contamination". According to this threat model, an organism that is taken to Mars or any other celestial object from Earth ends up mutating in the new environment into something entirely different and is transported back to Earth.

"We introduce a microbe to Mars or another extraterrestrial body, and it subsequently mutates and evolves functional distinctiveness and then is brought back to Earth as a novel organism," Ricciardi told Space.com.

It is precisely this kind of cascading risk, he argues, that justifies extreme precautionary measures rather than dismissing back-contamination concerns as negligible.

NASA's recently announced moon base will span hundreds of square miles and be built in three phases, but biosafety infrastructure has not featured in those plans.