Astronomy 2232F/G Lecture Notes - Lecture 8: Tectonics, Galilean Moons, Tidal Locking

• School: Western University
• Department: Astronomy
• Course: Astronomy 2232F/G
• Professor: Gordon Osinski

Document Summary

Io: most volcanically active body in solar system, plumes rise 300km above surface, sulfur (causes colouring of moon) and silicate lavas - basalt, thin, temporary atmosphere: sulfur dioxide, no impact craters young age of surface. Active volcanism: volcanic vent grown in size in 2 years. Volcanic landforms: patera steep sided, flat floors, calderas over 200, lava flows and lakes, volcanic ash plains produced from large eruptions. What composition of magma and eruption style: we do not see steep sided volcanos syndicones and stratovolcanoes, suggests that magma is low viscosity and gentle eruption style, lavas are basaltic or sulfur rich. Umbrella shaped plumes: rise 300km above surface, up to 1000km wide, gases and coarse to fine-grained material. Tvashtar volcano: eruption on surface, seen on new horizon spacecraft, plume extends 330km above surface. Impact craters: haven"t seen any impact craters, surface estimated to be < 1 million yo - young, resurfacing rate ~1m/1000 years most geologically active in solar system.