1.  Johannes Kepler was born on December 27, 1571, in the town of Weil der Stadt, which then lay in the Holy Roman Empire, and is now in Germany.  When Johannes was about five years old, his father, Heinrich Kepler, was killed in Holland fighting as a mercenary. His mother, Katharina, was a herbalist who helped run an inn owned by her father.  Physically Damaged, Intellectually Strong The young Johannes Kepler was prone to ill-health. His hands were crippled and his eyesight permanently impaired by smallpox.  In 1594, aged 23, Kepler became a lecturer in astronomy and mathematics at the Protestant School in the city of Graz, Austria.  In 1596, at the age of 25, he published a book – Mystery of the Cosmos. His book explained why, logically, the sun lay at the centre of the solar system. A 1610 portrait of JOHANNES KEPLER by an unknown artist

2.  Kepler’s Second Law – The Law of Areas In 1602, Kepler deduced what came to be called his second law: a line drawn from planet to sun sweeps out equal areas in equal times.  Kepler’s First Law – The Law of Orbits Kepler tried to figure out the mathematical shape of Mars’s orbit. After about 40 misses, in 1605, he got it right. Mars follows an elliptical path around the sun.  And now he formulated what would become Kepler’s first law: planets orbit the sun in ellipses, with the sun at one focus.  Kepler’s Third Law – The Law of Periods In 1618, his continuing research led to his third law of planetary motion.  Last days of Kepler’s life- Kepler moved around a lot during the last few years of his life. His job as a mathematician disappeared and, in an effort to make ends meet, he ended up casting horoscopes for a military commander – General Wallenstein.  Johannes Kepler died after falling ill at the age of 58, on November 15, 1630 in the German city of Regensburg

3. Johannes Kepler- Place and Time in which he lived Lived 1571 to 1630. In Kepler’s lifetime:  religion clashed with religion  religion clashed with science  the old ideas of Ptolemy and Aristotle clashed with the new discoveries of Copernicus and Galileo CopernicusGalileo  the superstition of astrology clashed with the science of astronomy MORE ABOUT THE LIFE, CULTURE AND INTERESTS OF JOHANNES KEPLER Kepler reflected the times he lived in. Seen through modern eyes, he had somewhat contradictory ideas. He was:  an unorthodox Protestant  a follower of Copernicus and Galileo  a brilliant mathematician and scientist who discovered that the solar system’s planets follow elliptical paths, not circular paths  an astrologer, whose horoscopes were sought out as among the best available  Astronomy, astrology, mathematics and natural philosophy were the fields in which Kepler worked but he became very famous for Kepler's laws of planetary motion and Kepler conjecture Astronomyastrologymathematicsnatural philosophyKepler's laws of planetary motionKepler conjecture

4. Although Johannes Kepler is known mainly for his work in discovering the three laws of planetary motion, he has made many other significant contributions to mathematics. Gave first proof of how logarithms work with his Rudolphine Tables (1624). Discovered two new regular polyhedra (1619). Did important work with optics including: the first, correct mathematical theory of the camera obscura (telescope), and the first correct explanation of the workings of the human eye (1604, 1611). Designed a new type of telescope. The Keplerian or astronomical telescope was the first to use two convex lenses. Gave first mathematical explanation of close packing of equal spheres (which led to an explanation of the shape of cells of a honeycomb, 1611). Published many influential works including: "Mystery of the Cosmos", "The Harmony of The World", and the Rudolphine Tables. All of Kepler's contributions helped in the fulfilment of his dearest wish, to help establish Copernicanism. This would, in turn, give proof (mathematically) of how the universe operates.