So my 8 year old educated me this week. Turns out that the hot-ness of a planet is not entirely correlated with its proximity to the sun. She had to do a little project on Venus and it turns out that's the hottest planet.

Seems odd that Mercury, which millions of miles closer to a massive fireball burning at about a jillion degrees Fahrenheit would be less hot.

Initial research suggest that the reason for this is Venus's very thick atmosphere that retains heat. But if that's the case....wouldn't Venus have just incinerated itself? Or is that actually what's happening...it' just takes a long time? Is venus burning up?