Post Lot Text
First edition, definitive issue including Kepler's 4-leaf supplement of directions (signed q4), Sportula Genethliacis missa de Tabularum Rudolphi usu in Computationibus Astrologiciis (printed in Sagan, Prussia, 1629), and Philippus Eckebrecht's world-map based on the Rudolphine tables, Nova orbis terrarum delineatio, engraved at Nuremberg by J.P. Walch in 1630 (perhaps distributed even later). It does not include the appendix by Jacob Bartsch found in a few copies. The first quire is found here in its first state, the second quire in second state. Fine copy, with the frontispiece of astronomers in the Temple of Urania and the important world-map in brilliant impressions.
The last of Kepler's works to appear in his lifetime and his crowning achievement, "the chief vehicle for the recognition of his scientific accomplishments" (Gingerich). These planetary tables in the form of a perpetual calendar, which allows any position to be determined for any date in the past or future, were based on Tycho Brahe's observations, supplemented by Kepler's own. On his deathbed Brahe had charged Kepler with completing and publishing his long-projected astronomical tables, to be named after their patron, Emperor Rudolph II. Kepler's calculations represented a formidable achievement as Brahe's data, based on imaginary perfect circular orbits, had to be reinterpreted according to the planets' true elliptical orbits, which Kepler himself had discovered. In order to achieve this accuracy, Kepler improved on Napier's and Ursinus's logarithms and created his own logarithmic tables (see lot 103) for use in the complex calculations of planetary orbits.