ASTRO-110 Lecture Notes - Lecture 16: Runaway Greenhouse Effect, Impact Crater, Solar Wind
Document Summary
Very little large scale cratering visible: erased by geological activity. Venus is nearly as large as the earth, and like the earth, it"s still geologically active, but there are differences: Like earth and mars, venus got its atmosphere through volcanic. Water in the atmosphere was dissociated by ultraviolet light just as on mars, Unlike mars, continuing volcanism on venus replenishes any atmosphere that is. Although venus has a thick atmosphere, it has very weak surface winds. Venus has a shit ton of volcanoes. Impact crater ripped apart by tectonic stresses. Longest channel in the solar system is made out of lava. This, and the lack of water on venus, accounts for the lack of erosion on its surface. So why do we see so few craters? there are very few small craters because small impactors burn up in the thick atmosphere before they hit the ground.
