If it's in small amounts, sure. Mercury has little patches of ice on a rocky surface, that sublimates and gets redeposited in permanently shadowed parts of craters at the poles. But the entire surface here is made of ice, so as the temperature increased the entire dayside surface would start to sublimate. After a short while there'd be a thin atmosphere of gas above the surface so it wouldn't be exposed to vacuum anymore, and as it kept on building up and thickening the pressure would increase and protect the rest of the sublimating molecules from the melting surface from escaping into space (even on the dark side). This being a 2G world I think it'd be able to retain enough gases to prevent refreezing on the night side.
Ice World at 415K - ??
- Thread starter BaldEagle
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If it's in small amounts, sure. Mercury has little patches of ice on a rocky surface, that sublimates and gets redeposited in permanently shadowed parts of craters at the poles. But the entire surface here is made of ice, so as the temperature increased the entire dayside surface would start to sublimate. After a short while there'd be a thin atmosphere of gas above the surface so it wouldn't be exposed to vacuum anymore, and as it kept on building up and thickening the pressure would increase and protect the rest of the sublimating molecules from the melting surface from escaping into space (even on the dark side). This being a 2G world I think it'd be able to retain enough gases to prevent refreezing on the night side.
Running the numbers, as it stands there's no good reason why this world DOESN'T have an atmosphere. it's 18.5 earth masses, 3750 kg/m³ density, clearly an earth-sized rocky core (maybe up to double the radius of Earth even) with a few thousand km of ice on top. It also is massive enough to retain hydrogen gas and anything heavier (even on its eccentric orbit where the blackbody temperature ranges between 333 and 544 K at closest and furthest approach). The ice surface should be molten and the resulting gases would be a thick atmosphere (probably mostly water vapour, CO2, and nitrogen). The surface ocean would probably be about 20-30 km thick and then under that would be a range of high pressure ices over a few thousand km, with a rocky "core" 1-2 times bigger than the Earth itself (itself divided into a rocky mantle and iron core) below.
So yeah, it's definitely Stellar Forge being inaccurate again.
So yeah, it's definitely Stellar Forge being inaccurate again.
It's only 16 ls from an F-class star. Stellar winds could strip that atmosphere, particularly if it has no magnetic field.
Eh? It's 178ls from a K V star, if the first pic on the thread is to believed? I'm talking about that, not Qoefi LU-D d13-53 . That one's even more ridiculous since it's hot enough to melt most kind of rock there. It may yet be massive enough to hold onto its atmosphere though since it's 57 earth masses - but it might be somewhat 'puffy'.
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We're discussing the one in post #18 (or so I thought)
