It's funny you ask that, because it's a NASA engineer who told me this; "there are only 4 things controlling the heating and cooling of the earth and don't believe anything else. Earth gets closer to sun the earth warms, earth moves away from sun, earth cools. Sun warms earth warms, sun cools earth cools. Nothing else matters." My sun completed in first robotics in HS, their team was guided by NASA, the engineer who designed the robonaut was man who told me this... Team 118 if you want to look it up. Funny.