Life on Earth might actually be Martian — or Europan, or Titanese. Or maybe our ancestors came from outside our solar system, flung up from a distant planet (perhaps Caprica?) billions of years ago and migrated to Earth. It all sounds far-fetched, but new research suggests microbes can survive an asteroid impact big enough so send them into space, making panspermia — the idea that we're all really aliens at heart — a real possibility.
Previous experiments have shown that microbes can survive in the punishing cold of space. Their ability to hide out in a rock's interior, safe from a vacuum is well-documented too.
But scientists haven't been able to tell whether hearty critters could survive the heat and crushing force of an asteroid impact that would be needed to eject them into space in the first place. Astrobiologists at the Institute of Aerospace Medicine in Germany have finally connected all the dots with a new experiment in the Spring issue of Astrobiology Magazine
And what better way to simulate an asteroid impact than to smash rocks together? That's exactly what the scientists involved in this research did, after sprinkling test rocks with bacteria known live inside stone, some cyanobacteria, and a dash of lichen onto them. All three lifeforms survived the high-speed collision, suggesting they could be floating through outer space even now, waiting for a chance encounter with distant planet to plant the seeds of a whole new 'alien' biosphere.
Source: Astrobiology Magazine