GEO 1111 Lecture Notes - Lecture 2: Spiral Galaxy, Liquid Hydrogen, Runaway Greenhouse Effect

• School: University of Ottawa
• Department: Geology
• Course: GEO 1111
• Professor: Mark Charette

Document Summary

Lecture 2: solar system and origin of the earth. Consists of our star (the sun), the planets, their satellites and asteroids. Proposed by aristotle, however not believed by the church. Challenged by aristarchus, simple sphere and sun and planets rotating around the earth. Retrograde motion; refers to motion in the direction opposite to the movement of something else. Depending on the speed of another planet, it may seem like planets are moving backwards. One of its basic ideas was that planets were carried on a small circle (called the epicycle, whose center moves along another, larger, circle around the earth, called the deferent. largest retrograde, so closest to the earth. Saturn has the smallest so it is a lot farther from the earth. Also suggest earth"s spins leaning on an axis sunrise to. *compared to astronomy, geology is a very young science. Dominated by gases and low density (hydrogen, helium)