page_title: Johannes Kepler
section_title: Rudolphine Tables and his last years
hierarchical_section_title: Johannes Kepler / Linz and elsewhere (1612–1630) / Rudolphine Tables and his last years
caption_attribution_description: English: Tabulae Rudolphinae, quibus astronomicae scientiae, temporum longuinquitate collapsae Restauratio continetur; A Phoenice illo Astronomorum Tycho Ex Illustri &amp; Generosa Braheorum in Regni Daniae familiâ oriundo Equite,..., Jona Saurius (= Saur, Johann, Sauer, Johannes; Saurius, Johannes), Ulm 1627. The title page of Johannes Kepler's Rudolphine Tables (1627), the most accurate and comprehensive star catalogue and planetary tables published up until that time. It contained the positions of over 1000 stars and directions for locating the planets within our solar system. Kepler finished the work in 1623 and dedicated it to his patron, the Emperor Rudolf II, but actually published it in 1627. It is the first scientific work which extensively employs the new concept of logarithms. The table's findings support Kepler's laws and the theory of a heliocentric astronomy.
context_page_description: Johannes Kepler was a German astronomer, mathematician, and astrologer. He is a key figure in the 17th-century scientific revolution, best known for his laws of planetary motion, and his books Astronomia nova, Harmonices Mundi, and Epitome Astronomiae Copernicanae. These works also provided one of the foundations for Newton's theory of universal gravitation.
  Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein.
  Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting telescope, and was mentioned in the telescopic discoveries of his contemporary Galileo Galilei. He was a corresponding member of the Accademia dei Lincei in Rome.
  Kepler lived in an era when there was no clear distinction between astronomy and astrology, but there was a strong division between astronomy and physics.
context_section_description: In 1623, Kepler at last completed the Rudolphine Tables, which at the time was considered his major work. However, due to the publishing requirements of the emperor and negotiations with Tycho Brahe's heir, it would not be printed until 1627. In the meantime, religious tension – the root of the ongoing Thirty Years' War – once again put Kepler and his family in jeopardy. In 1625, agents of the Catholic Counter-Reformation placed most of Kepler's library under seal, and in 1626 the city of Linz was besieged. Kepler moved to Ulm, where he arranged for the printing of the Tables at his own expense.
  In 1628, following the military successes of the Emperor Ferdinand's armies under General Wallenstein, Kepler became an official advisor to Wallenstein. Though not the general's court astrologer per se, Kepler provided astronomical calculations for Wallenstein's astrologers and occasionally wrote horoscopes himself. In his final years, Kepler spent much of his time traveling, from the imperial court in Prague to Linz and Ulm to a temporary home in Sagan, and finally to Regensburg. Soon after arriving in Regensburg, Kepler fell ill. He died on 15 November 1630, and was buried there; his burial site was lost after the Swedish army destroyed the churchyard. Only Kepler's self-authored poetic epitaph survived the times:
  Mensus eram coelos, nunc terrae metior umbras
  Mens coelestis erat, corporis umbra iacet.
  I measured the skies, now the shadows I measure
  Skybound was the mind, earthbound the body rests.
caption: Title page of the Tabulae Rudolphinae, Ulm, 1627
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