After reading an article from the Astrobiology Magazine website, I find it fascinating that panspermia, a hypothesis that life came from space, could actually be true. Of course, this has always been a well considered hypothesis. Though, scientists have always questioned: if life (ex: bacteria) were to exist on an asteroid, could it survive the extreme temperatures and the radiation from the sun? What about the  Earth’s atmosphere and the force caused by the impact? Even though Dina Pasini, a researcher with the European Planetary Science Congress at UCL, could not answer all these questions, her research did prove to be useful.

Using frozen algae organisms, Pasini tested whether such simple life forms could survive impacts at extreme speeds. Using a light gas gun, she fired bullets of organisms at 6.93 km/s into water. Even at that speed, some organisms still survive. A typical meteorite impacting Earth would likely have similar speeds, showing that life could survive the initial impact. With regards to freezing and radiation, if organisms were embedded deep in ice or rock, it could protect it from the temperature and radiation. Moreover, passing through Earth’s atmosphere would only create heat on a thin surface layer of the asteroid, again protection any life forms within the asteroid.

Even though this test does not accurately recreate an actual meteor impact,  it shows that panspermia is possible after all. This also implies and raises many questions. First of all, we could all potentially be aliens. But more importantly, if we find extraterrestrial life, they could be related to us. And if life came from some other planet, we must stem from some other species. Are humans considered a primitive species in the eyes of others? Do some other species stem from us?

http://www.astrobio.net/pressrelease/5687/could-life-have-survived-a-fall-to-earth