Its crazy to think its all actually out there

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marcus
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Ryan, most likely you saw the indication of surface water ice in a crater at the Moon's south pole. Some space junk was crashed into the crater and sent up a plume of material including water vapor.

Polar craters can be among the coldest places in the solar system because they are open to the dark sky and so can radiate all their heat out into space, but (assuming neglible axial tilt) they never get any sunlight. So if there is no atmosphere to carry heat in, the pit of the crater in permanent darkness can achieve a very low equilibrium temp.

Ceres has an axial tilt of about 2 degrees. Earlier I encountered the conceptual problem that (at least at the equator in full sunlight) ice would begin to sublime when exposed to vacuum. So if you scrape off a patch of surface layer (e.g. carbonate etc. rocky material) you get sublimation.

However I guess that a natural or artificial crater near Ceres pole would not have this problem, and would give a structurally safe access to the putative ice mantle.

You mentioned the interest of working through problems and I agree. There are a lot of elementary (one could say even pedagogically useful) problems in basic physics chemistry and biology which immediately appear when one transfers context.

Not all the problems are grimly serious ones :biggrin:, one can for instance ask how far could I jump? Say I live in a large artificially lit cavern with 3% earth gravity. So if my mass is 200 pounds my weight is 6 pounds. How do I keep physically fit? Would it be possible to fly? (say with a couple of hand-powered propellers?) Would I be able to jump long distances?
 
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