My characters use the ship's maser to melt a small glacier on a frozen chunk of rock way the hell out in the middle of deep space. Would the ice instantly boil into steam due to the lack of atmospheric pressure? And once steam, would that create an atmosphere that will prevent further melted water from boiling instantly?
I've been studying Wikipedia's physics articles now for hours, and I am so confused. Any help would be great! Thanks!
----------
0 / 50,000
Mrt 17, 2008 - 14 24
I'm not entirely sure if the ice would sublime or not but I don't think it would, I think it would go to liquid water first. As for the steam creating an atmosphere, I'm pretty sure it wouldn't work like that. If it's a fairly small chunk of rock, it wouldn't have enough of a gravitational field to hold any sort of atmosphere.
0 / 50,000
Mrt 17, 2008 - 17 00
If there's no atmospheric pressure, the molten ice would indeed become steam right at 0°.
And, if there's no actual gravity on the rock, then the steam wouldn't create an atmosphere, and just dissipate even more and more within the emptiness of space.
101,289 / 50,000
Mrt 18, 2008 - 13 19
Thanks for the replies. The rock is a bit bigger than Pluto, and Pluto has an atmosphere during periapsis. Not much of one.
But mass doesn't seem to be a primary factor in the presence of an atmosphere. Consider Mercury, which has no atmosphere, is about twice the size of Titan, which has a huge atmosphere.
Would this make any difference? Would it make any difference if they kept using the maser to keep the water warmish?
50,251 / 50,000
Mrt 19, 2008 - 08 36
Mercury is too close to the sun and lacking in gravity to retain an atmosphere. Titan is losing its atmosphere as well, due to its low gravity, but its distance from the sun causes this to be a slower process. Additionally, volcanic outgassing can supply an atmosphere for longer periods of time - Mars doesn't have sufficient gravity to hang on to much of an atmosphere, but when it was still tectonically active it replaced what it was losing at a high enough rate to have liquid water at its surface. If you're using a laser at a constant rate to melt water, then you might be able to compensate for loss.
Most loss is caused by solar winds, I think, so the further from the sun, the more likely it will retain an atmosphere. Also makes it more likely to be largely icy - ice is found in larger amounts further from the sun.
51,851 / 50,000
Apr 5, 2008 - 01 28
"Consider Mercury, which has no atmosphere, is about twice the size of Titan, which has a huge atmosphere."
Sorry, just got to comment on this - Titan is actually bigger than Mercury. It's 5,150 km across, compared to Mercury's 4,879 km. (Earth's moon is at 3,474 km.) However, Mercury has about twice the MASS of Titan. You need to be very careful when you talk about size, because its physical size doesn't always mean it'll have the same equivelant mass.