Johannes Kepler

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Johannes Kepler (1571-1630) was a German astronomer and mathematician most famous for creating what was up to that point the most accurate model of planetary astronomy with his three laws of planetary motion. Kepler was the first to present a coherent theory that the planets move around the Sun in elliptical orbits, that the speed of each planet varies, and that the Sun is responsible for that variation.

More about: Johannes Kepler


  • 1571 - 1630
    Life of the German astronomer Johannes Kepler.
  • 27 Dec 1571
    Johannes Kepler is born in Weil der Stadt, Germany.
  • 1594
    Johannes Kepler is appointed the official instructor in astronomy and mathematics at the University of Graz, Austria.
  • 1597
    Johannes Kepler marries a rich widow, Barbara Müller.
  • 1597
    Johannes Kepler publishes his Mysterium Cosmographicum (The Cosmographical Mystery), which endorses the heliocentric model of Copernicus.
  • 1598
    Johannes Kepler moves to Prague to work at the court of Rudolph II.
  • 1604
    Johannes Kepler presents his theory of light being focused by the lens onto the retina in his Supplement to Witelo.
  • 1609
    Johannes Kepler publishes his Astronomia Nova (The New Astronomy).
  • 1609
    Johannes Kepler discovers that Mars has an eliptical orbit around the Sun.
  • 1611
    Johannes Kepler writes the treatise Dioptrics on the best optics for an astronomical telescope.
  • 1619
    Johanees Kepler publishes his De Harmonices Mundi (Harmonies of the World).
  • 1627
    Johannes Kepler publishes his Rudolphine Tables.
  • 15 Nov 1630
    Johannes Kepler dies of illness in Regensburg.