Quick Facts
Rheticus also spelled:
RhƤticus, or Rhetikus
Original name:
Georg Joachim De Porris, or Von Lauchen
Born:
February 16, 1514, Feldkirch, Austria
Died:
December 5, 1574, Kassa, Hungary (now KoŔice, Slovakia) (aged 60)
Subjects Of Study:
Copernican system
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Georg Joachim Rheticus

Austrian astronomer
Also known as: Georg Joachim De Porris, Georg Joachim RhƤticus, Georg Joachim Rhetikus, Georg Joachim Von Lauchen(Show More)

Georg Joachim Rheticus (born February 16, 1514, Feldkirch, Austria—died December 5, 1574, Kassa, Hungary (now KoÅ”ice, Slovakia)) was an Austrian-born astronomer and mathematician who was among the first to adopt and spread the heliocentric theory of Nicolaus Copernicus.

In 1536 Rheticus was appointed to a chair of mathematics and astronomy at the University of Wittenberg. Intrigued by the news of the Copernican theory that Earth revolves around the Sun, he went to Frauenburg (now Frombork, Pol.) in 1539, where he studied for two years with Copernicus. Rheticus published the first account of the new views in his De libris revolutionum…Nic. Copernici…narratio prima… (1540; ā€œThe First Account of the Book on the Revolutions by Nicolaus Copernicusā€). He encouraged Copernicus to complete his great work and took it to Nürnberg for publication, though in 1542 he moved to Leipzig to take up a new appointment before it was actually printed.

From his stay at Wittenberg until his death, Rheticus also worked on his great treatise, which was completed and published after his death by his pupil Valentin Otto as Opus Palatinum de triangulis (1596; ā€œThe Palatine Work on Trianglesā€). The treatise contains tables of values for the trigonometric functions (of an arc or angle) computed in intervals of 10 seconds of arc and calculated to 10 decimal places.

Equations written on blackboard
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The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Erik Gregersen.
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