Georg Purbach (also Georg von Peuerbach, Peurbach, Purbach, Purbachius, his real surname is unknown) (born May 30, 1423 in Purbach near Linz– April 8, 1461 in Vienna) was an Austrian astronomer/astrologer and mathematician. A family name, or surname, is that part of a persons name that indicates to what family he or she belongs. ... May 30 is the 150th day of the year in the Gregorian calendar (151st in leap years). ... Events July 31 - Hundred Years War: Battle of Cravant - The French army is defeated at Cravant on the banks of the river Yonne. ... Purbach can refer to: Purbach am Neusiedlersee — a town in Burgenland, Austria Purbach — a place in Austria at Purbach — a large lunar crater located in the southern highlands of the Moon People with the name Purbach include: Georg Purbach — an Austrian astronomer and mathematician This is a disambiguation page: a... Map of Austria, locating Linz Linz is a city and Statutarstadt in northeast Austria, on the Danube river. ... April 8 is the 98th day of the year in the Gregorian calendar (99th in leap years). ... Events February 2 - Battle of Mortimers Cross - Yorkist troops led by Edward, Duke of York defeat Lancastrians under Owen Tudor and his son Jasper Tudor, Earl of Pembroke in Wales. ... Vienna (German: Wien [viːn]; Slovenian: Dunaj, Croatian and Serbian: Beč Romanian: Viena, Hungarian: Bécs, Czech: Vídeň, Slovak: Viedeň, Romany Vidnya, Russian: Вена) is the capital of Austria, and also one of the nine States of Austria. ... An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ... An astrologer, in modern times, is a person who practices a form or forms of astrology; in earlier times, they were observer of the stars. ... Leonhard Euler is considered by many people to be one of the greatest mathematicians of all time A mathematician is a person whose primary area of study and research is mathematics. ...

He is credited with the invention of several scientific instruments, including the regula, the geometrical square, and the "Jacob's Staff." The Purbach crater on the Moon is named after him. For the the plant known as the ocotillo, sometimes called the Jacobs staff, see ocotillo. ... Purbach is a large lunar crater located in the rugged southern highlands of the Moon. ... Bulk composition of the moons mantle and crust estimated, weight percent Oxygen 42. ...

About the year 1440 he received the degree of master of philosophy and the free arts, cum insigni laude, at the University of Vienna. His teacher in mathematics was probably Johann von Gmünden. For alternative meanings, see number 1440. ... University of Vienna, main building, seen from Beethovens apartment The University of Vienna (German: Universität Wien) in Austria was founded in 1365 by Rudolph IV and hence named Alma mater Rudolphina. ...

In 1448 he went on a trip to Italy for the sake of study. There, Giovanni Bianchini of Ferrara and Cardinal Nicholas of Cusa, then in Rome, became interested in the young man and induced him to lecture on astronomy at the University of Ferrara. He refused offers of professorships at Bologna and Padua, and also the appointment as court astronomer to King Ladislaus of Hungary, but went back to Vienna in 1450 to teach. He lectured on philology and classical literature. His scientific teaching was done chiefly in private, his most famous pupil being Johann Müller of Königsberg, later known as Regiomontanus. Events January 5/ 6 - Christopher of Bavaria, Norway and Sweden dies with no designated heir leaving all three kingdoms with vacant thrones. ... Giovanni Bianchini (in Latin, Johannes Blanchinus) (1410-ca. ... Ferrara is a city, an archiepiscopal see in Emilia-Romagna, Italy, capital city of the province of Ferrara. ... Nicholas of Cusa Nicholas of Cusa (1401 – August 11, 1464) was a German cardinal of the Catholic Church, a philosopher, jurist, mathematician, and an astronomer. ... City motto: Senatus Populusque Romanus – SPQR (The Senate and the People of Rome) Founded 21 April 753 BC mythical, 1st millennium BC Region Latium Area  - City Proper  1285 km² Population  - City (2004)  - Metropolitan  - Density (city proper) 2,553,873 almost 4,300,000 1. ... The University of Ferrara (Università degli Studi di Ferrara) is main university of the city of Ferrara in the Emilia-Romagna region of northern Italy. ... Bologna (pronounced , from Latin Bononia, BulÃ¥ggna in the local dialect) is the capital city of Emilia-Romagna in northern Italy, between the Po River and the Apennines. ... Location within Italy Tronco Maestro Riviera: a pedestrian walk along a section of the inland waterway or naviglio interno of Padua The city of Padua (Lat. ... Ladislaus Posthumus (22 February 1440 - 23 November 1457), Archduke, king of Hungary as László V (or VI); king of Bohemia as Ladislav I; duke of Austria, the only son of Albert II, Holy Roman Emperor, and of Elizabeth, daughter of the emperor Sigismund, was born at Komarom four months... Vienna (German: Wien [viːn]; Slovenian: Dunaj, Croatian and Serbian: Beč Romanian: Viena, Hungarian: Bécs, Czech: Vídeň, Slovak: Viedeň, Romany Vidnya, Russian: Вена) is the capital of Austria, and also one of the nine States of Austria. ... Events March - French troops under Guy de Richemont besiege the English commander in France, Edmund Beaufort, Duke of Somerset, in Caen April 15 - Battle of Formigny. ... Johannes Müller von Königsberg (June 6, 1436 – July 6, 1476), known by his Latin pseudonym Regiomontanus, was an important German mathematician, astronomer and astrologer. ...

Purbach has been called the father of observational and mathematical astronomy in the West. He began to work up Ptolemy's Almagest, replacing chords by sines, and calculating tables of sines for every minute of arc for a radius of 600,000 units. This was the first transition from the duodecimal to the decimal system. His observations were made with very simple instruments, an ordinary plumb-line being used for measuring the angles of elevation of the stars. Cardinal Bessarion invited him to Rome to study Ptolemy in the original Greek and not from a faulty Latin translation. He accepted on condition that Müller go with him. On account of the master's death the pupil went alone to complete the work. Claudius Ptolemaeus (Greek: ; c. ... Almagest is the Latin form of the Arabic name (al-kitabu-l-mijisti, i. ... In mathematics, the trigonometric functions are functions of an angle, important when studying triangles and modeling periodic phenomena. ... Johannes Bessarion, or Basilius (c. ...

Purbach is also noted for his great attempt to reconcile the opposing theories of the universe, the so-called homocentric spheres of Eudoxus of Cnidus and Aristotle, with Ptolemy's epicyclic trains. This work, *Theoricæ, etc., had an enormous success and remained the basis of academic instruction in astronomy until years after Copernicus had swept away all these hypotheses. Eudoxus of Cnidus (Greek Εύδοξος) (410 or 408 BC - 355 or 347 BC) was a Greek astronomer, mathematician, physician, scholar and friend of Plato. ... Aristotle (Ancient Greek: AristotelÄ“s 384–March 7 322 BCE) was an ancient Greek philosopher, a student of Plato and teacher of Alexander the Great. ...

He worked at the Observatory of Oradea/Nagyvarad in Transylvania and established in his "Tabula Varadiensis" this Transylvanian town's observatory as laying on the prime meridian of Earth.

Twenty works of him are known. Among these, the following are the most important:

• Theoricæ novæ planetarum, id est septem errantium siderum nec non octavi seu firmamenti (1st ed., Nuremberg, 1472, by Regiomontanus; followed by many others in Milan and Ingolstadt);
• Sex primi libri epitomatis Almagesti, completed by Regiomontanus (Venice, 1496; Basle, 1534; Nuremberg, 1550);
• Tabulæ eclypsium super meridiano Viennensi (2nd ed., Vienna, 1514);
• Quadratum goemetricum meridiano (Nuremberg, 1516);
• Nova tabula sinus de decem minutis in decem per multas, etc., completed by Regiomontanus (Nuremberg, 1541).

This article incorporates text from the public domain Catholic Encyclopedia. Johannes Müller von Königsberg (June 6, 1436 – July 6, 1476), known by his Latin pseudonym Regiomontanus, was an important German mathematician, astronomer and astrologer. ... Johannes Müller von Königsberg (June 6, 1436 – July 6, 1476), known by his Latin pseudonym Regiomontanus, was an important German mathematician, astronomer and astrologer. ... The public domain comprises the body of all creative works and other knowledge—writing, artwork, music, science, inventions, and others—in which no person or organization has any proprietary interest. ... The Catholic Encyclopedia (also referred to as the Old Catholic Encyclopedia today) is an English-language encyclopedia published in 1913 by the The Encyclopedia Press, designed to give authoritative information on the entire cycle of Catholic interests, action and doctrine. // History The writing of the encyclopedia began on January 11...