Venus's albedo is so high that the insolation at the surface is even less than Earth's. Yet it's hotter than Mercury, which is closer to the sun than Venus. Th

Venus's albedo is so high that the insolation at the surface is even less than Earth's. Yet it's hotter than Mercury, which is closer to the sun than Venus. The article says that volcanism is the reason, and that solar heating would not cause this result on its own, even though it's everyone's first guess.