In the third episode of Star Trek: Discovery, the spacecraft’s resident mushroom expert, astromycologist Lieutenant Paul Stamets, casually references a bizarre-sounding theory as he argues to Michael Burnham that there’s no difference between biology and physics at the quantum level.

“You talk about spores — what are they? They are the pro-generators of panspermia,” says Stamets. “They are the building blocks of energy across the universe. Physics and biology? No. Physics as biology.”

Arguing that “spore-producing structures” are what hold the galaxy together, Stamets brings up “panspermia,” the idea that life spread through space because of microbes and living organisms that hitched a ride on meteorites, asteroids, comets, and space debris. Wild as it sounds, it’s actually a real space theory that scientists are currently investigating. They argue that it’s certainly possible that once something like a microbe-infested meteorite makes an impact on a new planet, it can seed life there.

Burnham finds Stamet's spores experiment.

While panspermia is very much a theory and not a proven science fact, there is a growing body of scientific evidence that supports its predictions. It may seem hard to believe that any form of life could survive the harsh reality of space as well as the colossal impact of a space-rock crash, but scientists have speculated that some organisms can endure that journey — especially if they are buried beneath the surface of the rock.

It so happens that many real-life scientists would agree with Star Trek’s Lieutenant Stamets on the type of organism that’s best suited to panspermia: spores. Specifically, bacteria that form spores and can survive extremely low temperatures and live within rock for millions of years.

Whether spore bacteria could actually survive those conditions, however, is debatable: In 2001, researchers from the German Aerospace Center published a paper in the Origins of Life and Evolution of Biospheres in which they showed that, when they stuck a type of bacterium found in soil and the gastrointestinal tract of humans onto the Russian Earth-orbiting FOTON satellite for two weeks, their survival depended on how the spores were protected.

“The data suggests that in a scenario of interplanetary transfer of life, small rock ejecta of a few centimeters in diameter could be sufficiently large to protect bacterial spores against intense insolation, however, micron-sized grains, as originally requested by panspermia, may not provide sufficient protection for spores to survive,” they wrote.

In 2015 researchers from the Russian Academy of Sciences tried this experiment again, but with a landing module with the same velocity as a meteorite. After 45 days of orbital flight and a high-impact landing, four out of the 24 bacterial spore samples survived.

Lt. Paul Stamets, the astromycologist.

Statistical models, meanwhile, provide more promising support for panspermia enthusiasts support for panspermia enthusiasts: In 2015, Harvard scientists created a model showing that, “under certain conditions, panspermia leads to statistical correlations in the distribution of life in the Milky Way.” In 2017, the same scientists built a different model showing that panspermia was even more likely to have occurred in the TRAPPIST-1 system compared to previous Earth-to-Mars panspermia theories. They argued that They argued that it’s very likely that microorganisms naturally colonized planets via ejected space rocks but note that actual surveys of biosignatures will be required to support this theory.

In Star Trek, panspermia may hold the key to, as Stamets puts it, discovering the “vein and muscles that hold our galaxies together.” On our planet, we’d be lucky to find out if it explains why we’re alive at all.

If you liked this article, check out this video on Inverse’s review of Star Trek Discovery.