Hurkyl said:
First off, there is little to no environment to fight on the moon. I don't see any reason to think that there is a less hostile environment than the moon; sure it's dry and barren, but there's no duststorms, no icequakes, no volcanoes, and you're not surrounded by toxic liquids/gasses.
Thirdly, consider resources. It's a lot easier to resupply and maintain a moon base than it would be a Callisto base.
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Hello Hurkyl, didnt see til now you'd replied on this thread
Your arguments can be turned around to suggest sending robot probes to land on Callisto
Personally I think the surface of Callisto (4th Galilean moon out, less magnetic bother) is dry and barren
I believe the Callisto crust is estimated to be very thick (not like europa which is speculated to have an ocean under moderate ice crust)
I personally do not expect any atmosphere, no toxic gas, no dust storm, no volcano, probably no ice-quake either.
But you are right that it is good to KNOW for sure. So let us send some probes to Callisto surface.
Personally i don't expect there is a lot of environment to "fight", as you say, but let's find out.
I suspect that Callisto looks and feels rather like Luna except that the surface rock is chemically easier to use. The surface rock is made of rocket fuel, that is it is largely H2O. That (besides being scientifically more interesting and in a more interesting location) is a big advantage Callisto has over Luna.
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You make a big point about cost. You also make a point about learning and practice and experience. It is an appealing thought that Luna missions could be seen as practice for Callisto.
You are doubtless mostly right about cost----however cooling the power reactor might not be so costly, replacing oxygen losses might not be so costly, replacing water losses might not be as difficult as on the moon.
the main reply to the cost point, though, is what do you get for your money? IMHO a boondoggle base on the moon with make-work "science" experiments for astronauts risking their lives for no real benefit---unless it counts as practice.
Versus IMHO a really exciting new experience, engaging the intense interest of first-rate people, and a fascinating thing for the rest of us to share in as the adventure unfolds.
You see, hurkyl, the screen saver on this old monitor is the Jovian moons/
I just have to stop typing and they come on/
it zooms down towards the surface of Callisto/
so I can't forget