Panspermia is the only biological term I can think of which sounds more like a title of a high concept porn flick with a sci-fi theme. But behind the odd name lies a curious concept that if proven true, could mean that we have common ancestors not just in the deep past but on strange worlds across the cosmos. If some species of bacteria somehow seeded millions of worlds, it may have evolved into other creatures on other planets while staying unchanged on its home world as a living fossil. Of course that mysterious “some how” is what makes many scientists think twice about the viability of panspermia.
The odds of a big enough asteroid slamming into a planet with organisms that can survive an unprotected spaceflight like Earth’s tardigrades, launching them towards a solar system tens or even hundreds of light years away at just the right angle and at just the right quantity to get to a planet where these organisms can thaw and start evolving are, well staggering. This is why most scientists today note that panspermia is a curious concept, that would be incredibly exciting if true, but think that life most likely appears on a planet which can support it with a solvent and an energy source (i.e. food and water).
However, recent experiments which launched tough creatures from our own world into space and safely brought them back, the case of Earth bacteria surviving on the Moon and numerous complaints from NASA engineers about how hard it is to sterilize equipment and avoid almost inevitable contamination of other worlds with Earth germs got me thinking. If life is billions of years old and we think that the oldest planets we can hypothesize of are more than twice as old as the Earth, could there have been in all the vastness of space other civilizations sending a few probes carrying tough organisms from their planets into deep space and seeding worlds as they go? Having a sort of intelligent dispersion of life would guarantee that the bacteria will get to a planet or a moon and as it would make sense to send probes to look for alien life, all these probes are highly likely to be sent to worlds more or less hospitable to living things.
If that sounds like an even bigger stretch than random meteor impacts, consider what we want to do in the next thousand years. We want to change Mars to be more like Earth. We want to go and explore habitable environments in our solar system with contaminated probes. We want to send robotic explorers to other planets to find alien life and those explorers will also carry our germs among the stars. Could we eventually be responsible for panspermia events when our technology becomes advanced enough to freely move around space? Maybe life in the universe could be a combination of organic components coming together in the right environments, natural seeding and intelligent dispersal of a space faring species that just cant clean its space probes well enough? Certainly something to ponder when we explore the cosmos