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Kepler


http://en.wikipedia.org/wiki/File:Johannes_Kepler_1610.jpg










  • Johannes Kepler
  • A German scientist
  • Lived from 1571 to 1630 AD
  • Famous for Kepler's Laws, three laws regarding orbits and satellites 4 , 5




Kepler's Laws

  1. "Planets move in elliptical orbits with the Sun at one focus."5
  2. Law of Equal Areas:  "A line drawn between the sun and a planet sweeps out equal areas during equal intervals of time."6 As shown in the drawing to the right.
  3. Harmonic Law:  "The square of a planet's orbital period is proportional to the cube of the semimajor-axis length."6


http://bdaugherty.tripod.com/gcseAstronomy/kepler.html