ASTRON 10 Lecture Notes - Lecture 15: Cirrus Cloud, Solar Wind, Nitrous Oxide
Document Summary
Original atmosphere was very similar to the solar nebula. Hydrogen, helium blew away through the solar wind. Most of this left the solar system entirely, some became part of the gas giants. Occurred in the first 0. 5 billion years of earth"s history. Occurred when crust was solidifying, but core was super hot. Oxides erupted onto the surface through volcanoes. Water, laughing gas and other nitric oxides, carbon dioxide and. Nitric oxides are the source of earth"s nitrogen atmosphere, though it"s unclear about how this occurred. One way it could have happened is that life broke it down into baser components, then suffocated after they got rid of most of the nitric oxides. Created by photorespiring life (plants, bacteria, some protists) Released oxygen into the atmosphere, took the carbon compounds and built themselves out of it. Side fact: chemotrophic life was seen as earliest form of life. Oxygen gas is very reactive, meaning something must be continually creating it.
