Johann Kepler, born 1571; school at Maulbronn, 1586; University of Tübingen, 1589; M.A. of Tübingen, 1591; Professor at Gratz, 1594; "Prodromus," with "Mysterium Cosmographicum," published 1596; first marriage, 1597; joins Tycho Brahe at Prague, 1600; death of Tycho, 1601; Kepler's optics, 1603; Nova, 1604; on Comets, 1607; Commentary on Mars, including First and Second Laws, 1609; Professor at Linz, 1612; second marriage, 1613; Third Law discovered, 1618; Epitome of Copernican Astronomy, 1618-1621; Rudolphine Tables published, 1627; died, 1630.