Lunar Water

[jjohnson]

I was wondering why water ice on the Moon, in the permanently shadowed craters around the poles, wouldn't just sublime in the low pressure and low temperatures there. A quick search of some NASA sites indicated that temperatures inside those craters should never exceed 100K, or about -280°F. There's part of the answer, of course, but not all the answer. Water ice can change from a solid directly into a vapor state, a process called sublimation, under the right conditions, so I googled water phase diagrams, and got this.

All that's left is to see if the Moon's pressure is such that sublimation could occur at or below 100K. It doesn't look like it to me, but then, the pressure scale (Y-axis) stops at a low of 0.1 pascal (Pa) so there is some "dark graph" area remaining below that, eh?

A little more research on Moon pressure would be welcome.

Jim

[katesisco]

The compression of our heliosphere via neutron energy into Fluff is making flashes visible on the Moon because the moon needs an atmosphere for that to happen, even so small. It is making the unknown little details of how things work on the molecular level clear. This compression is how we were born. How we were made human. It is the Eden time of Earth. If Fluff were not here, as it was not 10 m y ago, we wouldn't have the compression of our heliosphere.

We didn't arrive on the scene until about this time in our history coincidentally. But our system was getting energy input just the same. Maybe from our galactic center from a GRB. Or maybe there in some unknown input on a 50,000 y cycle. Our discovered history is full of zap-the-Earth cycles: 5,000, 26,000, 50,000 and what-all else.

Our Deep Hot Biosphere is alive and vibrant. T Gold said the Ice Ball Earth theory explains the 90 degree flip over 1/2 billion years ago. Our entire history is one of change. There is no status quo. Planets come, planets go. All intelligence is local.

Yes, our future may be one in which our H2O is reticent to part itself from the rivers of moisture in the sky. Has happened before. Egyptian mythology says Nut has to hold up the sky from the Earth. Not to mention our rendition of what happens when the H2O returns to a parched Earth.

But as the song says: I don't want to hear the best years are behind me. So we have theories that all conspire to invalidate the Second Law, and we are its best evidence.

Which is why I say Venus is for Vesuvians.