Newton’s version of Kepler’s Laws
Recall Kepler’s laws were empirical
- explained observed orbits of 6 known planets
- also fit newly discovered Neptune, Uranus, and Pluto
- also fit comet orbits, i.e. Halley’s Comet
- in modified form fit Galilean satellite orbits
Newton could derive them from his laws of motion and gravity, leading to a deeper understanding
- Leading to
- weighing everything in the Universe
- concept of escape velocity and space probes
K I -- ellipses
- The Greeks and Kepler wondered what kept the planets going
- Newton and Galileo showed that continued motion was natural. It was the curve in the path that required a force, the force of gravity.