The planets and dwarf planet Pluto are shown in their correct order of distance from the sun, their correct relative sizes and their correct relative orbital distances. The sizes of the bodies are greatly exaggerated relative to the orbital distances.
Venus ranks No. 1 for average temperature because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead (3,280 degrees Celsius). Don't try to visit.
Mercury rotates slowly and has a thin atmosphere, and consequently, the night-side temperature can be more than 5,000 degrees lower than the dayside temperature. On Mercury, you either freeze or roast, period.
Earth, well, you know.
For the rest of the story: http://www.lifeslittlemysteries.com/201-how-hot-are-the-planets-in-our-solar-system.html