ASTR 101 Lecture Notes - Lecture 7: Planetary Science, Earth Mass, Galilean Moons

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

Document Summary

There are 8 major planets with nearly circular orbits. Dwarf planets are smaller than the major planets and some have quite elliptical orbits. Planets all orbit in the same direction and nearly in the same plane. We can learn more about a world like our earth by studying it in context with other worlds in the solar system. Stay focused on processes common to multiple worlds instead of individual facts specific to a particular world. Comparing the planets reveals patterns among them. Those patterns provide insights that help us understand our own planet. Made mostly of h/he (98%-2%) gas (plasma) Converts 4 million tons of mass into energy each second. Made of metal and rock; large iron core. Very hot, very cold: 425 (day), -150 (night) Nearly identical in size to earth, surface hidden by clouds. Hellish conditions due to an extreme greenhouse effect. Even hotter than mercury, 470 , day and night. Average density 5. 52g/cm3, average temperature: 290 k.