Earth Sciences 1086F/G Lecture Notes - Lecture 9: Planetesimal, Tempel 1, Orbital Eccentricity
15 Apr 2016
School
Department
Course
Professor
Document Summary
Named after the roman god, is the rst rock from the sun , has no natural satellites and is small. Always stays in the same region of the sky as the sun which makes it hard to see from earth, never gets closer than 80 million km from us. The only spacecraft to have made a close approach to mercury was mariner 10 and almost all our knowledge comes from the three passes it mad in 74 and 75. Much of our current data is based on data from messenger which launched in. 2004, which entered orbit around mercury on march 18, 2011 and mapped the entire planet until it crashed into the surface on april 30, 2015 after completing 4104 orbits. Similar to the moon: for both, rotation has been altered by tidal attraction, surfaces are heavily cratered, large craters are ooded by ancient lava ows, both are small, airless, and have ancient, inactive surfaces.
