Sonoma State University Astronomy 100
J.S. Tenn

The Copernican Revolution

1543Nicolaus Copernicus publishes De Revolutionibus (translation) with dedication to the Pope, dies.
1572Tycho Brahe observes supernova, demonstrates lack of parallax, becomes famous.
1576-97Tycho observes, plots positions of planets at Uraniborg Observatory and Stjerneborg Observatory on isle of Hveen, Denmark (now Ven, Sweden). Galileo Galilei does experiments in mechanics, becomes professor of mathematics at Pisa in 1589 at age 25.
1600Johannes Kepler, 29, meets Tycho, 53, in Prague.
1601Tycho dies. Kepler acquires data, becomes Imperial Mathematician.
1604Kepler observes supernova, takes time out from study of orbits.
1609Kepler publishes Astronomia Nova (A New Astronomy) containing 1st and 2nd laws. Galileo builds telescope and observes sky.
1610Galileo publishes Sidereus Nuncius (Starry Messenger or Message). Kepler defends it without having seen telescope.
1616Galileo travels from Florence to Rome to convert Church to Copernican system. Result is that Copernicus is put on Index of forbidden books and Galileo is prohibited from teaching or defending heliocentric model.
1619Kepler publishes Harmonices Mundi (Harmony of the World) containing 3rd law.
1629-32Galileo publishes Dialogue Concerning the Two Chief World Systems. Five months after publication it is banned and Galileo summoned to Rome. He goes. Kepler dies in 1630.
1633Galileo is convicted of disobedience, confined to house arrest, forbidden to publish anything.
1638Galileo publishes Two New Sciences in Holland.
1642-43Galileo dies. Isaac Newton is born.
1664-65Plague closes Cambridge. Newton goes to country, discovers laws of motion and gravity, explains orbits, invents calculus, makes discoveries in optics.
1682Edmond Halley, with Newton's aid, has plotted orbits of comets. He shows that comet of 1682 is same as that of 1531 and 1607, predicts return in 1758.
1687 Newton publishes Principia (Mathematical Principles of Natural Philosophy) containing laws of motion and gravitation and explaining motions in the sky and on earth with the same laws.
1727Newton dies. Alexander Pope writes
   Nature and Nature's laws lay hid in night;
   God said, Let Newton be! and all was light.
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