I started thinking about the problem of finding places in the Solar System where humans could live. The main problems are 1) energy sources, 2) sources of water and oxygen, and 3) protection from energetic cosmic rays.

Assuming Europa does have a global subsurface ocean, wouldn't this ocean provide all of the things mentioned above?

Also, a refuge of human knowledge (and perhaps terrestrial life) deep in Europa's oceans would survive most of the disasters that could wipe out life on Earth, including close supernovae events and exposure to catastrophic cosmic / gamma ray events. It would take an *awful* lot of energy to strip the ice off of Europa's oceans, I would think.

Perhaps, in the name of the survival of humanity, you could make a case for placing a colony within Europa's oceans...?

-the other Doug

I'm not sure there's an energy source under the ice that would be economically viable unless we get that fusion thing working.

A very tricky problem, however, would be to get people TO Europa. That's a whopping load of radiation you encounter on the way in. Even a few hours would be way past lethal. And getting meters of lead shielding to park inside Jupiter's gravity well would cost more than a little propulsion.

You might have to have human embryos make the trip and grow them in vitro once they're there.

There's a lot of the solar system that's explorable with "2001 A Space Odyssey" class nuclear powered vehicles using "CASIMIR" type relatively high-thrust ion/plasma propulsion. (or the equivalent) But getting deep into Jupiter's radiation belts is enormously not trivial and will take enormously non-trivial amounts of extra mass as shielding.

Any manned exploration beyond Mars and Near Earth Asteroids and the Inner Belt will require such capabilities at a minimum, AND truely low cost transport to either low Earth orbit, or space-elevator transport to geostationary orbit.

Hate to say it, but JR's right on. I don't think that the Jovian system is a good place for people to be just because of that fearsome radiation hazard. Even if the destination was Callisto, you'd still presumably have to pass through the hot zone at least once during the capture maneuver. Only way I could ever see even visiting there would be if some sort of magic radiation-deflecting force field were ever invented (with LOTS of fail-safe design features!)

Titan, now...that might be a different story.

I found two interesting articles about radiation-deflecting magnetic bubbles. I would like to post links to them but am not sure what forum to make use of.

I'd say the Manned spaceflight forum to be honest.

DOug

Okay, thanks.