Hot Planets

Being the nerdy sciency type, i've been watching a documentary on the solar system. It reminded me about the planet Venus.


As we know from school, Venus is about halfway between Mercury (average temperature 167°C) and Earth (15°C). So we might expect Venus to be somewhere between fifty and a hundred. However, with an atmosphere composed mostly of carbon dioxide, the average Venusian temp is 464°C.
[source: NASA planetary data sheet]