Johannes Kepler

T J Osler

Johannes Kepler (pronounced /ˈkɛplɚ/) (December 27, 1571 – November 15, 1630) was a German mathematician

, astronomer and astrologer, and key figure in the 17th century scientific revolution

The Great Comet of 1577, which Kepler witnessed as a child, attracted the attention of astronomers across Europe

• In astronomy, Kepler's three laws of planetary motion are:

• "The orbit of every planet is an ellipse with the sun at a focus."

• "A line joining a planet and the sun sweeps out equal areas during equal intervals of time."[1]

• "The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit."

Five Platonic Solids

Kepler's Platonic solid model of the Solar system from Mysterium Cosmographicum (1600)

Closeup of inner section of the model

A plate from Astronomiae Pars Optica, illustrating the structure of eyes

Diagram of the geocentric trajectory of Mars through several periods of retrograde motion.Astronomia

nova, Chapter 1, (1609).

Karlova street in Old Town, Prague – house where Johannes Kepler lived

Geometrical harmonies in the perfect solids from Harmonices Mundi (1619)

The iconic frontispiece to the Rudolphine Tables celebrates the great astronomers of the

past:Hipparchus, Ptolemy, Copernicus, and most prominently, Tycho Brahe

See http://www.hps.cam.ac.uk/starry/ for details of above.

Kepler's horoscope for General Wallenstein

The GDR stamp featuring Johannes Kepler.

10 euro Johannes Kepler silver coin