Johannes Kepler | Biography, Discoveries, & Facts

On December 27, 1571, Johannes Kepler, German astronomer (discovered laws of planetary motion), was born in Weil der Stadt, Holy Roman Empire (d. 1630). From the article:

"Johannes Kepler | Biography, Discoveries, & Facts
Johannes Kepler, (born December 27, 1571, Weil der Stadt, Württemberg [Germany]—died November 15, 1630, Regensburg), German astronomer who discovered three major laws of planetary motion, conventionally designated as follows: (1) the planets move in elliptical orbits with the Sun at one focus; (2) the time necessary to traverse any arc of a planetary orbit is proportional to the area of the sector between the central body and that arc (the “area law”); and (3) there is an exact relationship between the squares of the planets’ periodic times and the cubes of the radii of their orbits (the “harmonic law”). Kepler himself did not call these discoveries “laws,” as would become customary after Isaac Newton derived them from a new and quite different set of general physical principles. He regarded them as celestial harmonies that reflected God’s design for the universe. Kepler’s discoveries turned Nicolaus Copernicus’s Sun-centred system into a dynamic universe, with the Sun actively pushing the planets around in noncircular orbits. And it was Kepler’s notion of a physical astronomy that fixed a new problematic for other important 17th-century world-system builders, the most famous of whom was Newton.

Kepler's theory of the solar system.
Kepler's theory of the solar system. Encyclopædia Britannica, Inc.
Top Questions
What was Johannes Kepler’s profession? When and how did it begin?
Johannes Kepler was an astronomer. He originally studied to be a theologian at the University of Tübingen. He became very interested in astronomy, and his math professor Michael Maestlin encouraged his interest. Maestlin was an early believer in Nicolaus Copernicus’s idea that Earth and the other planets move around the Sun. He taught Kepler all about Copernicus’s ideas.

Where was Johannes Kepler born?
Johannes Kepler was born on December 27, 1571, in the town of Weil der Stadt in the duchy of Württemberg, now in Germany.

How and where did Johannes Kepler die?
After contracting a fever, Johannes Kepler died on November 15, 1630, in Regensburg, in the duchy of Bavaria, now in Germany. He had gone to Regensburg to collect interest on Austrian bonds he had. His grave was destroyed only a few years after his death during the Thirty Years’ War.

Among Kepler’s many other achievements, he provided a new and correct account of how vision occurs; he developed a novel explanation for the behaviour of light in the newly invented telescope; he discovered several new, semi-regular polyhedrons; and he offered a new theoretical foundation for astrology while at the same time restricting the domain in which its predictions could be considered reliable. A list of his discoveries, however, fails to convey the fact that they constituted for Kepler part of a common edifice of knowledge. The matrix of theological, astrological, and physical ideas from which Kepler’s scientific achievements emerged is unusual and fascinating in its own right. Yet, because of the highly original nature of Kepler’s discoveries, it requires an act of intellectual empathy for moderns to understand how such lasting results could have evolved from such an apparently unlikely complex of ideas. Although Kepler’s scientific work was centred first and foremost on astronomy, that subject as then understood—the study of the motions of the heavenly bodies—was classified as part of a wider subject of investigation called “the science of the stars.” The science of the stars was regarded as a mixed science consisting of a mathematical and a physical component and bearing a kinship to other like disciplines, such as music (the study of ratios of tones) and optics (the study of light). It also was subdivided into theoretical and practical categories. Besides the theory of heavenly motions, one had the practical construction of planetary tables and instruments; similarly, the theoretical principles of astrology had a corresponding practical part that dealt with the making of annual astrological forecasts about individuals, cities, the human body, and the weather. Within this framework, Kepler made astronomy an integral part of natural philosophy, but he did so in an unprecedented way—in the process, making unique contributions to astronomy as well as to all its auxiliary disciplines."