... in a livable planet may not be so improbable. I think NASA has a plausible program for investigating this possibility. And I don't think a few manned space missions will do it. Hundreds of tiny robotic missions is the way to go. The Hoyle panspermia idea is nonsense. But note your two examples small objects from the Moon or Mars - both with less gravity than the earth. I ...

... this summer is the use of advanced underwater exploration technology to enable investigators to study previously inaccessible specimens," says Williams. "Now we're able to use Rover-type subs with robotic arms similar to what is envisioned for exploring the lunar surface." Pavilion Lake is located about 500 kilometres north of Vancouver in Marble Canyon Provincial Park. It was formed by a...