Just as there are the Newtonian Laws for motion of a particle, there are laws for the motion of planets. These laws were created by Johannes Kepler. Johannes Kepler was raised in a very poor lifestyle, having a father for only the first few years of his life and a mother accused of witchcraft. With him doing well in school, he was able to go to college in the late 1580's to early 1590's and then receive a job teaching at the University of Graz. There he taught mathematics and astronomy, even though he knew little about those, since he studied to be a Lutheran pastor. After a few years teaching, he wrote a book and afterwards became more interested in astronomy. It was at this time he came up with Kepler's Laws of Planetary Motion.
I. The orbits of the planets are ellipses with the sun at one focus.
II. A line from a planet to the sun sweeps over equal areas in equal intervals of time
III. A planet's orbital period squared is proportional to its average distance from the sun cubed : Py^2=Dau^3
Now looking at the laws; if a planet has a distance of 13 AU away from the sun, how long would the period for that planet be in years?
No comments:
Post a Comment