What is panspermia?
The Panspermia is a hypothesis that describes life on earth as not originated from the planet. The thought is that the first living beings that colonized the earth came from outer space, from other planets or even from other galaxies by traveling in comets, meteorites and so on. According to this hypothesis even the kind of life now existent on earth could have also been seeded intentionally by extraterrestrial beings in other stellar and planetary systems.