Scientists examining salt crystals deep in a salt mine in Kansas has discovered a bacterium that is 250 million years old -- 100 million years older than the dinosaurs.

Bacteria have the ability to go into a kind of semi-permanent hibernation, but survival for this long was unheard of. After lying dormant in the salt crystal for 250 million years, the scientists added fresh nutrients and a new salt solution, and the ancient bacteria "re-animated."

Dr. Russell Vreeland, one of the biologists who found the bacteria, pointed out that bacteria can survive the forces acceleration via rubble thrown into space via a meteor impact. If it is possible for a bacteria to survive being off the planet and to stay alive within a salt chunk for 250 million years, then in a sort of "reverse-exogenesis" it may be possible that earth's own microbes are already out there.