First of, Venus is the hottest, and yes I can explain why: The Greenhouse Effect. Basically, Venus has a fuc-, erm, a substantial amount of CO2 gas which interferes with the atmospheres ability to filter rays from the sun. I know, I was surprised too when I first figured this out. http://www.astronomytoday.com/astronomy/venus.html http://timesofindia.indiatimes.com/home/sunday-times/Why-is-Venus-the-hottest-planet-even-though-Mercury-is-closest-to-the-Sun/articleshow/1823345.cms Second, it is in fact in the game, but it's only a multiplayer map at the moment. According to people, the Traveler helped make planets in the solar system more habitable.