Why is the energy radiated from earths surface not all lost into space?
Some energy that the earth radiates is, indeed, radiated out into space. If it weren’t, then you would not be able to SEE the earth because no light would be radiating from it. As the one poster put it in a reasonable manner, the atmosphere contains 78% nitrogen, 21% oxygen, 0.93% argon, 0.038% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%. Energy is radiated from the earth in a very wide spectrum. Some of this energy lies in the visible region (light), and the part of that that gets through the atmosphere is what you would see if you were in orbit. Part of the radiation is infrared (heat) – it is this radiation that is contained by the atmosphere and helps keep the planet warm (planets with no atmosphere are VERY cold).
