Quote:
Originally Posted by eburacum45
Make the planet closer to the sun, and larger; this will allow the atmsphere to remain dense despite being much hotter. A Venus-like (Cytherean) world with about 1.5 gees at Mercury's distance could be very hot on the surface; bigger planets would be even worse. Ultimately the atmosphere will have silicon vapour clouds as well as, or instead of sulphuric acid clouds. The night side would probably glow, as well. But perhaps we should make up a new name for such hellish worlds.
One planet which might resemble a superVenus in some ways is Gliese 876d;
http://en.wikipedia.org/wiki/Gliese_876_d
it has a mass of around 7.5 Earths, and is almost certainly molten on the surface thanks to tidal heating if not because of any potential greenhouse effect. |
About Gliese 876, well, I think the conditions there must be extremely hellish.Tidal heating 10000-100000x stronger than on Io, maybe high pressure water-CO2 greenhouse atmosphere....That planet must be hotter than some red dwarf stars on the surface, I would guess
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Btw there would be a very big region of distances and temperatures, from around 80 to 900 degress Celsius in the upper atmosphere (Venus has much lower temperatures in the cloud layer) where no condensate could be and so these world will be cloudless, the question is; would the surface be seen as blurred because even without clouds the 90-100 bar atmosphere scatters the light or would be the surface not seen at all because the atmosphere will scatter the light to that point when the sky would be pure white and so the planet will be seen from space as white, with a thick blue border because of the Rayleigh scattering?