ASTB03H3 Lecture : Lecture 3
Document Summary
Analyzed brahe"s data for mars (brahe died) Came up with the idea of elliptical orbits. Circles from the center, every point on the circle is at an equal distance. 2 focal points the further these points are, the flatter, the ellipse: a semi-major axis plays the role of the radius, eccentricity a major of how flat the ellipse is. Found that mars and earth orbited in this pattern. Galileo galilei: the larger the orbit, the longer the period (time for one orbit) It means there"s a predictable pattern of the planets. Kepler didn"t know absolute sizes of orbits but still tried to find principles to explain why the orbits were the way they were. Suggests that physical force is responsible for orbits. Produces rudolphine tables to predict motion of planets: tables of planet position back in the day were not working. Prediction of where planets would be at different points in time (days of the year)
