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Kepler's laws, along with Newton's law of gravitation, describe the motions of planets and other orbiting objects. Kepler's first law states that planets follow elliptical orbits around the Sun, with the Sun at one focus. Kepler's second law states that the line from the planet to the Sun sweeps out equal areas in equal times. Kepler's third law relates orbital period to distance from the Sun.

Sections:
00:00 - Intro
00:27 - The Sun wobbles
01:33 - Elliptical shape of orbits
02:17 - Eccentricity and foci of an ellipse
03:51 - Seasons are NOT due to elliptical orbits
04:31 - Kepler's first law
05:11 - Planet's speed throughout an elliptical orbit
08:01 - Kepler's second law
10:31 - Kepler's third law
12:59 - Summary

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