Johannes Praetorius or Johann Richter (1537 – 27 October 1616) was a Bohemian German

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

and

astronomer An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...

Life

Praetorius was born in

Jáchymov Jáchymov (; or ''Joachimsthal'') is a spa town in Karlovy Vary District in the Karlovy Vary Region of the Czech Republic. It has about 2,300 inhabitants. Jáchymov has a long mining tradition, thanks to which it used to be the second most popu ...

Bohemia Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...

. From 1557 he studied at the

University of Wittenberg Martin Luther University Halle-Wittenberg (), also referred to as MLU, is a public research university in the cities of Halle and Wittenberg. It is the largest and oldest university in the German state of Saxony-Anhalt. MLU offers German and i ...

, and from 1562 to 1569 he lived in

Nuremberg Nuremberg (, ; ; in the local East Franconian dialect: ''Nämberch'' ) is the Franconia#Towns and cities, largest city in Franconia, the List of cities in Bavaria by population, second-largest city in the States of Germany, German state of Bav ...

. His astronomical and mathematical instruments are kept at

Germanisches Nationalmuseum The ''Germanisches Nationalmuseum'' is a museum in Nuremberg, Germany. Founded in 1852, it houses a large collection of items relating to German culture and art extending from prehistoric times through to the present day. The museum is Germany' ...

in Nuremberg. In 1571 he became Professor of mathematics (astronomy) at

Wittenberg Wittenberg, officially Lutherstadt Wittenberg, is the fourth-largest town in the state of Saxony-Anhalt, in the Germany, Federal Republic of Germany. It is situated on the River Elbe, north of Leipzig and south-west of the reunified German ...

where he met Valentinus Otho and Joachim Rheticus. He died in

Altdorf bei Nürnberg Altdorf bei Nürnberg ( , ; ) is a town in south-eastern Germany. It is situated east of Nuremberg, in the district Nürnberger Land. Its name literally means “Altdorf near Nuremberg”, to distinguish it from other Altdorfs. History Altdorf ...

, aged about 79. He taught

Copernicus Nicolaus Copernicus (19 February 1473 – 24 May 1543) was a Renaissance polymath who formulated a mathematical model, model of Celestial spheres#Renaissance, the universe that placed heliocentrism, the Sun rather than Earth at its cen ...

' theory of astronomy initially as a means of eliminating the

equant Equant (or punctum aequans) is a mathematical concept developed by Claudius Ptolemy in the 2nd century AD to account for the observed motion of the planets. The equant is used to explain the observed speed change in different stages of the plane ...

from

Ptolemy Claudius Ptolemy (; , ; ; – 160s/170s AD) was a Greco-Roman mathematician, astronomer, astrologer, geographer, and music theorist who wrote about a dozen scientific treatises, three of which were important to later Byzantine science, Byzant ...

's account, and later moving to a proto-

Tychonic system The Tychonic system (or Tychonian system) is a model of the universe published by Tycho Brahe in 1588, which combines what he saw as the mathematical benefits of the Copernican heliocentrism, Copernican system with the philosophical and "physic ...

Works

* De cometis, qui antea visi sunt, et de eo qui novissime mense Novembri apparuit, narratio 1578 * Problema, quod iubet ex quatuor rectis lineis datis quadrilaterum fieri, quod sit in circulo 1598

References

Sources

* * Gerhard Bott (Hrsg.): ''Focus Behaim Globus.'' 2 Bde. Nürnberg: Verlag des Germanischen Nationalmuseums 1992 * Johann Gabriel Doppelmayr: ''Historische Nachricht von den Nürnbergischen Mathematicis und Künstlern.'' Nürnberg: Peter Conrad Monath 1730, S. 83-92 * * * Klaus Matthäus: Zur Geschichte des Nürnberger Kalenderwesens. Frankfurt a.M.: Buchhändler-Vereinigung 1969, Sp. 1044-1047 * Uwe Müller (Hrsg.): ''450 Jahre Copernicus „De revolutionibus“.'' Astronomische und mathematische Bücher aus Schweinfurter Bibliotheken. Schweinfurt: Stadtarchiv 1993 * Zofia Wardeska: ''Die Universität Altdorf als Zentrum der Copernicus-Rezeption um die Wende vom 16. zum 17. Jahrhundert.'' Sudhoffs Archiv 61/2, 1977, S. 156-164 * Georg Andreas Will: ''Nürnbergisches Gelehrtenlexikon Bd. 3.'' Nürnberg: Lorenz Schüpfel 1757, S. 225-231 * Helmar Junghans: ''Verzeichnis der Rektoren, Prorektoren, Dekane, Professoren und Schloßkirchenprediger der Leucorea vom Sommersemester 1536 bis zum Wintersemester 1574/75.'' In Irene Dingel, Günther Wartenberg: ''Georg Major (1502-1574) - Ein Theologe der Wittenberger Reformation.'' Evangelische Verlagsanstalt, Leipzig, 2005,

External links

*
Astronomie in Nürnberg

{{DEFAULTSORT:Praetorius, Johannes 1537 births 1616 deaths People from Jáchymov Mathematicians from Bohemia German Bohemian people University of Wittenberg alumni Academic staff of the University of Wittenberg 16th-century German astronomers 16th-century German mathematicians 17th-century German mathematicians Globe makers