Hottest possible terrestrial planet
I recently read this article (http://www.space.com/5985-hottest-planet-discovered.html) about a hot Jupiter that orbits it's star about once a (earth) day. This and remembering how high of an albedo Venus has (inefficient if you want to maximize temperature) made me think about how hot you could make a terrestrial planet, since I'm not sure of any observed terrestrial exoplanets that have all the right factors.
So for this question I am only accepting planets that one are terrestrial planets, two can survive and maintain their temperatures for billions of years. The planet's temperature will be considered based on surface temperature, I also want the planet to actually have a well defined surface, say something you could float a unobtainium boat on or whatnot.
Ideally I would prefer models that would make a reasonable person think that we should expect to eventually observe exoplanets with many of your stated properties. Though the specific perfect storm of properties might be extremely rare or whatnot requiring a perfect storm of variables, but they ought to be able to plausibly occur in our universe.
Some obvious (and less so) properties that would contribute to heat would be: Distance from star, extreme greenhouse effects, very high albedo, massive tidal effects from a dual planet system or massive moon or maybe the star itself at extremely close orbits, radioactive decay, and potentially multiple stars.
Problems that arise are that you would have to worry about much of the planet vaporizing at extremely high temperatures, and having a orbital period of one earth day is predicted to be about as close as you can get without being vaporized, though it might be different for a terrestrial planet.
Another problem is that thicker atmospheres grant greater greenhouse effects, however they are also likely to get blown away if close to the parent star, especially over the required geological timescales.
There's also the fact that the hottest stars wouldn't even last the required billions of years.
All in all it's more complicated than just maxing out every quality that we can know would increase temperature on it's own.
This post was sourced from https://worldbuilding.stackexchange.com/q/42647. It is licensed under CC BY-SA 3.0.
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