AST 248 Lecture Notes - Lecture 19: Biomineralization, Greigite, Divergent Evolution
Document Summary
Mass (1/10), radius (1/2) and atmosphere (. 7 . 9%(cid:895) s(cid:373)aller tha(cid:374) earth"s. Noachian epoch: before 3. 5 gyr; oldest surface features (tharsis bulge) and late, extensive water flooding. Hesperian epoch: between 1. 8 and 3. 5 gyr; formation of extensive lava plains. Amazonian epoch; after 1. 8 gyr; formation of olympus mons and other lava flows. Has craters and high volcanos (higher than on earth due to lower gravity). No active volcanos or geologic activity for last 1 2 byrs, due to low mass and therefore less radioactivity. Valles mariners is a large canyon (7 km deep, 100 km wide, stretches 1/4 across planet), formed by cracking of crust as mars cooled. Polar caps (h2o mostly, with surface co2) which grow and shrink according to the seasons. At(cid:373)osphere o(cid:374)ly 0. (cid:1011)% of earth"s, (cid:271)elo(cid:449) the triple poi(cid:374)t of (cid:449)ater, so (cid:374)o li(cid:395)uid (cid:449)ater possi(cid:271)le at any temperature. 95. 7% co2, 2. 7% n2, 1. 6% ar, 0. 2% o2, 0. 07% co, 0. 01% h 2o, 0. 01% no2.