ASTR 101 Lecture Notes - Lecture 31: James Lovelock, Gaia Hypothesis, Lynn Margulis

• School: Queen's University
• Department: Physics, Engineering Physics and Astronomy
• Course: ASTR 101
• Professor: David Alan Hanes

Document Summary

Venus is a near-twin of earth in size and mass. At times closest to earth, but hard to study. Learned about venus through radio telescopes, infrared detectors on earth, sending probes, landers, and so on. Surface of venus hot enough to melt lead. Clouds consist of sulphuric acid droplets; there is acid rain. The air pressure at the surface is around 90 x earth"s. This is like being 1 km deep in the ocean. (american sea wolf submarines have an estimated crush depth" limit of about 750 metres. ) It is not the clouds of venus but rather the thick co2 atmosphere that has led to runaway greenhouse effect. Indeed, the clouds reflect a lot of sunlight (so venus is very bright). The clouds actually reduce the amount of incoming radiation. The surface of venus is the same temperature everywhere, even though it rotates very slowly (and backwards, too, as it happens).