Mathematician:Johannes Kepler

Mathematician
German mathematician and astronomer best known nowadays for Kepler's Laws of Planetary Motion.

Inherited the papers of and spent many years analysing his observations, looking for patterns.

His most significant contribution to scientific thought was his deduction that the orbits of the planets are elliptical.

Also pre-empted the methods of integral calculus to find the volume of a solid of revolution by slicing it into thin disks, calculating the volume of each, and then adding those volumes together.

The foremost expert of his age on the of.

From an early age accepted the concept of the heliocentric universe of rather than the geocentric one of.

At one point earned a living (reluctantly) as an astrologer, a profession he despised.

Nationality
German

History

 * Born: 27 Dec 1571, Weil der Stadt, Württemberg, Holy Roman Empire (now Germany)
 * 1589: Studied mathematics at the under
 * 1591: Received Master's degree
 * 1594: Obtained position as lecturer in mathematics and astronomy in the Protestant seminary in Graz.
 * 1596: Wrote to, sending him a copy of his
 * 1598: Temporarily exiled from Graz on religious grounds
 * 1600: Became assistant to in Prague
 * 1601: Took over 's position as Imperial Mathematician to Emperor Rudolph II. Spent years analysing the orbit of Mars. Took up casting horoscopes in order to make ends meet.
 * 1609: Sent a copy of his to, who failed to recognise its importance
 * 1611: Kepler's son and wife died. Political changes exiled him from Prague.
 * 1613: Remarried
 * Died: 15 Nov 1630, Regensburg (now in Germany)

Theorems

 * Kepler's Laws of Planetary Motion
 * Kepler's Explanation for Spacing of Planets
 * Kepler-Poinsot Polyhedron (with )

Publications

 * 1596: (The Sacred Mystery of the Cosmos)
 * 1601: De Fundamentis Astrologiae Certioribus (Concerning the More Certain Fundamentals of Astrology)
 * 1604: Astronomiae Pars Optica (The Optical Part of Astronomy)
 * 1604: De Stella Nova in Pede Serpentarii (On the New Star in Ophiuchus's Foot)
 * 1609: (New Astronomy) (in which Kepler's First and Second Laws of Planetary Motion appeared)
 * 1610: Tertius Interveniens (Third-party Interventions)
 * 1610: Dissertatio cum Nuncio Sidereo (Conversation with the Starry Messenger)
 * 1611: Dioptrice
 * 1611: (On the Six-Cornered Snowflake)
 * 1613: De Vero Anno, quo Aeternus Dei Filius Humanam Naturam in Utero Benedictae Virginis Mariae Assumpsit
 * 1615: Eclogae Chronicae (published with Dissertatio cum Nuncio Sidereo)
 * 1615: (New Stereometry of Wine Barrels) (in which the techniques of integral calculus were foreshadowed)
 * 1618 -- 1621:
 * 1619: (The Harmonies of the World) (in which Kepler's Third Law of Planetary Motion appeared)
 * 1621: Mysterium Cosmographicum (The Sacred Mystery of the Cosmos) (2nd Edition)
 * 1627: Tabulae Rudolphinae (Rudolphine Tables)
 * 1634: Somnium (The Dream)

Notable Quotes

 * God lives in the details.


 * Geometry has two great treasures, one is the Theorem of Pythagoras, the other the division of a line into extreme and mean ratio; the first we may compare to a measure of gold, the second we may name a precious jewel.


 * A mind accustomed to mathematical deduction, when confronted with the faulty foundations of astrology, resists a long, long time, like an obstinate mule, until compelled by beating and curses to put its foot down into that dirty puddle.


 * Mother Astronomy would certainly starve if daughter Astrology did not earn the bread of both.