An analysis of a meteorite that hit Michigan in 2018 has revealed over 2,000 organic compounds. These are molecules that are precursors to life. The rock was recovered quickly, so there’s no chance that this is contamination.
This seems like a good opportunity to talk about panspermia.
What is Panspermia?
Panspermia is the basic hypothesis that life, or at least its building blocks, is literally everywhere in the universe.
Life on Earth actually started somewhere out there, and life from Earth will eventually seed other planets.
It sounds like science fiction, probably because science fiction has been very fond of the idea of intentional panspermia. This includes science fiction we’re all familiar with: To explain the fact that almost all the aliens in Star Trek are human-shaped (which is obviously because budget), somebody came up with the idea of the Progenitors, the oldest race in the universe, who got lonely and tinkered with the DNA on thousands of worlds to ensure that people like them would eventually evolve. Or something.
Panspermia, however, includes intentional transmission of life, but is not restricted to it; the primary mechanism is the movement of rocks from one system to another. Rocks such as the still somewhat mysterious ‘Oumuamua.
To proponents of the theory, the Michigan meteorite is good evidence.
Can We Prove It?
As of right now, not really. We have yet to find life on any planet other than Earth (and the phosphine on Venus turned out to be a false positive), although there’s some hope for certain outer system moons.
Even if we did, it would not prove panspermia on the wide scale. However, it might disprove panspermia by being so exotic it clearly didn’t come from the same organic molecules as life on Earth.
But panspermia within the solar system is not the same as between solar systems. Until and unless we manage to find life in another solar system that is remarkably similar to life here, we won’t know for sure.
Panspermia, for now, is not just unproven, but unprovable. But it has a certain appeal to it, especially in times when we question our own future.
It’s nice to think we might have relatives out there, isn’t it.