Johannes Kepler was born December 27, 1571 in Regensburg, Germany. Kepler's three laws of planetary motion can be summarized as follows:
(1) All planets move about the sun in elliptical orbits, having the sun as one focal point.
(2) A radius vector joining any planet to the sun sweeps out equal areas and equal lengths of time.
(3) The squares of the sidereal periods (of revolution) of the planets are directly proportional to the cubes of their mean distance to the sun.
Although Kepler is mainly remembered today for his three laws of planetary motion, these were only three pieces of a much broader spectrum for the search of harmony and celestial peace. Kepler was the first true Copernican after Copernicus himself. He found an astronomy clumsy with geometric errors and inconsistencies and changed it into an astronomy a hundred times more accurate.

Submitted by Josh Litalien