Difference between revisions of "Georg von Peuerbach" - New World Encyclopedia

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'''Georg von Peuerbach''' (also '''Georg Purbach''', '''Peurbach''', '''Purbach''', '''Purbachius''', his real [[surname]] is unknown) (born [[May 30]], [[1423]] in [[Purbach]] near [[Linz]] – [[April 8]], [[1461]] in [[Vienna]]) was an [[Austria]]n [[astronomer]] and [[mathematician]].  
+
'''Georg von Peuerbach''' (also '''Georg Aunpeckh''', '''Georg Purbach''', '''Peurbach''', '''Purbach''', '''Purbachius''', (born c. May 30, 1423 in Purbach near Linz – April 8, 1461 in [[Vienna]]) was an [[Austria]]n [[astronomy|astronomer]] and [[mathematics|mathematician]], considered a founder of observational and mathematical astronomy in the West. Peuerbach's best-known work, the ''Theoricae novae planetarum'' (1454; “''New Theories of the Planets''” ) suggesting that the planets' movement is governed by the sun, became an influential textbook of planetary theory, and by the late seventeenth century, had appeared in more than fifty [[Latin]], Hebrew and vernacular editions and commentaries. It influenced students such as [[Nicolaus Copernicus]] (1473–1543), [[Galileo Galilei]] (1564–1642), and [[Johannes Kepler]] (1571–1630).
  
He is credited with the invention of several scientific instruments, including the regula, the geometrical square. By several Purbach is also credited for the "[[Jacob's Staff]]" as well, but this is not plausible since the original Jacob's Staff was an instrument developed in the 1300's ,prior to his life time<sup>[http://www.surveyhistory.org/jacob's_staff1.htm]</sup>.The [[Purbach (crater)|Purbach crater]] on the [[Moon]] is named after him.
+
Peuerbach collaborated with his student and colleague [[Regiomontanus]] on a number of projects, including the observation of what came to be known as Halley's comet in 1456, and of a lunar eclipse on September 3, 1457, from a site near [[Vienna]]. At his death in 1461, he asked Regiomontanus to complete an abridgment of [[Ptolemy]]’s ''Almagest'', in which he calculated tables of sines for every minute of arc for a radius of 600,000 units, and introduced the use of  Hindu-Arabic numerals. He is credited with the invention of several scientific instruments, including the regula, the geometrical square. Peuerbach also served as a court [[astrology|astrologer]] for King Ladislaus V. Posthumus and, later, for Emperor Frederick III.
  
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.
+
==Life==
 +
'''Georg von Peuerbach''' was born Georg Aunpeckh at Peuerbach near Linz, sometime after 1421. His standard birthdate, May 30, 1423, is derived from a sixteenth-century horoscope. 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. He matriculated at the University of Vienna in 1446 and received his Bachelor of Arts in 1448. 
  
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 [[Ladislaus Posthumus of Bohemia and Hungary|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]].
+
From 1448 to 1450, he traveled in northern Italy. 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 lectured on astronomy in Padua, but  refused offers of professorships at Bologna and Padua.  He returned to Vienna, received his Master of Arts in 1453, and lectured on classical Latin poetry including [[Virgil]] and [[Juvenal]]. His scientific teaching was done chiefly in private, his most famous pupil being Johann Müller of Königsberg, later known as [[Regiomontanus]].
  
Purbach has been called the father of observational and mathematical astronomy in the West. He began to work up [[Ptolemy|Ptolemy's]] ''[[Almagest]]'', replacing chords by [[Sine (trigonometric function)|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.  
+
Peuerbach’s acquaintance with Johann Nihil, astrologer of Emperor Frederick III of Hapsburg, and his reputation as a mathematician and astronomer, led to his association with several royal courts as astrologer. Among his first patrons was the emperor’s nephew, young King Ladislaus V. Posthumus, who ruled lower Austria, Bohemia and Hungary until his early death in 1457. Subsequently he served Emperor Frederick III, who held court in Wiener Neustadt, near Vienna.
  
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.  
+
At that time, the Austrian universities were very conservative and regarded the humanities with suspicion. At the court of Emperor Frederick III, the humanist Enea Silvio Piccolomini, (later Pope Pius II) gathered a group of early German humanists who studied the classical Latin writers and lived according to the urbane style. This group included Georg von Peuerbach and his student, Johannes Regiomontanus. Peuerbach’s Latin love poems and letters were considered to be in the best Latin style. Peuerbach was instrumental in bringing about a relationship between the natural sciences and the humanities. Together with his teacher, Johannes von Gmunden, and his student and colleague, Regiomontanus (J. Müller), Peuerbach established the first School of Mathematicians at the University of Vienna and made mathematics an ancillary science of astronomy.
  
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.
+
Peuerbach collaborated with Regiomontanus on a number of projects, including the observation of what came to be known as Halley's comet in 1456, and of a lunar eclipse on September 3, 1457 from a site near Vienna. Peuerbach's best-known work, the ''Theoricae novae planetarum'' (1454; “''New Theories of the Planets''”), came from lectures which he gave to the Viennese “Citizens' School” (Bürgerschule), which Regiomontanus copied in his notebook. Peuerbach also computed an influential set of eclipse tables, ''Tabulae eclipsium'' (c. 1459), based on the thirteenth-century ''Alphonsine Tables'', that circulated widely in manuscript before the first Viennese edition in 1514. In 1460, at the behest of Cardinal Johannes Bessarion, Peuerbach began an epitome, or abridgment, of [[Ptolemy]]'s ''Almagest''. Cardinal Bessarion invited him to come to  Rome to study Ptolemy in the original Greek,instead of from a faulty Latin translation. Peuerbach accepted on the condition that Regiomonanus accompany him, but died in 1461 before the journey could be undertaken. At the time of his death, Peuerbach had finished only the first six (of thirteen) books; he asked Regiomontanus to completed the work (c. 1462), was was published in 1496 as ''Epytoma...in Almagestum Ptolomei''.
 +
 
 +
The Purbach crater on the [[Moon]] is named after him.
 +
 +
==Thought and Works==
 +
Peuerbach is considered a founder of observational and mathematical astronomy in the West. His work helped to pave the way for the Copernican conception of the world; he created a theory of planets, calculated tables of celestial eclipses, introduced the concept of the sine into trigonometry and invented a "quadratum geometricum" for measuring heights and distances.
 +
 
 +
In ''Epytoma...in Almagestum Ptolomei'' , the abridgment of [[Ptolemy|Ptolemy's]] ''Almagest'' which was completed by his student, [[Regiomontanus]], he replaced chords by [[trigonometry|sines]], and calculated tables of sines for every minute of arc for a radius of 600,000 units. He made his observations with very simple instruments, using an ordinary plumb-line to measure the angles of elevation of the stars. He also introduced a mathematical innovation by using Hindu-Arabic numerals in his sine tables, the first transition from the duodecimal to the decimal system. Peuerbach noted several errors in Ptolemy’s calculations, but remained a devotee of the ancient Greek mathematician.
 +
 
 +
Peuerbach worked at the Observatory of Oradea/Nagyvarad in Transylvania and established in his "''Tabula Varadiensis''" that this Transylvanian town's observatory lay on the prime meridian of Earth. He is credited with the invention of several scientific instruments, including the regula, the geometrical square. Some attribute the  "Jacob's Staff" to Peuerbach but this is an error, since the Jacob's Staff is kown to have been in use during the thirteenth century.  <sup>[http://www.surveyhistory.org/jacob's_staff1.htm]</sup>.
 +
 
 +
 
 +
=== ''Theoricae nova planetarum''===
 +
Peuerbach's best-known work, the Theoricae novae planetarum (1454; “New Theories of the Planets”) discussed the epicycle theory of the planets first presented by Ptolemy. Peuerbach attempted to reconcile the opposing theories of the universe, the so-called homocentric spheres of Eudoxus of Cnidus and [[Aristotle]], with [[Ptolemy]]'s epicyclic trains, with an assertion that the planets revolve in transparent but solid spheres. In spite of this erroneous notion, his suggestion that the planets' movement is governed by the sun was an early step toward the refutation of the geocentric  cosmology of  Ptolemy. Peuerbach said little about the planetary spheres themselves, but the illustrations in the original manuscript and in first printed edition show eccentric planetary models embedded within spherical shells, with inner and outer surfaces concentric to the earth. 
 +
 
 +
The first printed edition, in 1472, was the first product of  Regiomontanus’ printing press in Nuremberg. Erhard Ratdolt included it in the elementary astronomical compendia he published in Venice 1482 and 1486, which were widely imitated. By the sixteenth century it had become an influential textbook of planetary theory, displacing the widely used, anonymous thirteenth-century ''Theorica planetarum communis'' (the ''common “Theory of the Planets''”). By the late seventeenth century, Theoricae novae planetarum had appeared in more than fifty [[Latin]], Hebrew and vernacular editions and commentaries.  It introduced students such as [[Nicolaus Copernicus]] (1473–1543), [[Galileo Galilei]] (1564–1642), and [[Johannes Kepler]] (1571–1630) to an updated and simplified version of [[Ptolemy]]'s ''Almagest'' that gave a physical interpretation to its mathematical models. ''Theoricæ'' remained the basis of academic instruction in astronomy until Copernicus’ theories became widely accepted. 
 +
 
 +
=== Tabulae ecclipsium===
 +
 
 +
Among Peuerbach's early astronomical works was ''Tabulae ecclipsium'', which contained tables of his eclipse calculations. These were based on the thirteenth-century ''Alphonsine Tables'', and employed innovative, labor-saving organization to ease computational difficulties. It circulated widely in manuscript before its first publication in [[Vienna]] in 1514. Peuerbach later published additional tables and developed several astronomical instruments for making observations, as well as a large star globe.
 +
 
 +
===Works===
 +
Twenty of Peuerbach’s works are known; among these the following are the most important.  Peuerbach composed other treatises, most still in manuscript, devoted to elementary arithmetic, sine tables, calculating devices, and the construction of astronomical instruments (gnomons, astrolabes, and quadrants).
  
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);  
 
*''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);  
 
*''Sex primi libri epitomatis Almagesti'', completed by Regiomontanus (Venice, 1496; Basle, 1534; Nuremberg, 1550);  
Line 20: Line 42:
 
*''Quadratum goemetricum meridiano'' (Nuremberg, 1516);  
 
*''Quadratum goemetricum meridiano'' (Nuremberg, 1516);  
 
*''Nova tabula sinus de decem minutis in decem per multas, etc.'', completed by [[Regiomontanus]] (Nuremberg, 1541).  
 
*''Nova tabula sinus de decem minutis in decem per multas, etc.'', completed by [[Regiomontanus]] (Nuremberg, 1541).  
 +
==References==
 +
*Glick, Thomas F., Steven John Livesey, and Faith Wallis. 2005. ''Medieval science, technology, and medicine: an encyclopedia.'' ''Routledge encyclopedias of the Middle Ages'', 11. New York: Routledge. ISBN: 0415969301 9780415969307
 +
*Jaki, Stanley L. 1977. ''Planets and planetarians: a history of theories of the origin of planetary systems''. New York: Wiley. ISBN: 0470991496 9780470991497
 +
*Rommel, Otto. 1947. ''Wiener Renaissance''. Klassiker der Wiener Kultur, Bd. 1. Wien: Bellaria-Verlag.
 +
*Samhaber, Friedrich. 2000. ''Die Zeitzither: Georg von Peuerbach und das helle Mittelalter.'' [Raab]: Wambacher. ISBN: 3853600034 9783853600030
 +
*Strnadt, Julius. 1868. Peuerbach. Linz: [Druck von J. Wimmer].
  
 
== External links ==
 
== External links ==
* {{MacTutor Biography|id=Peurbach}}
 
 
*[http://www.univie.ac.at/hwastro Electronic facsimile-editions of the rare book collection at the Vienna Insitute of Astronomy]
 
*[http://www.univie.ac.at/hwastro Electronic facsimile-editions of the rare book collection at the Vienna Insitute of Astronomy]
  

Revision as of 14:53, 15 June 2007

Georg von Peuerbach (also Georg Aunpeckh, Georg Purbach, Peurbach, Purbach, Purbachius, (born c. May 30, 1423 in Purbach near Linz – April 8, 1461 in Vienna) was an Austrian astronomer and mathematician, considered a founder of observational and mathematical astronomy in the West. Peuerbach's best-known work, the Theoricae novae planetarum (1454; “New Theories of the Planets” ) suggesting that the planets' movement is governed by the sun, became an influential textbook of planetary theory, and by the late seventeenth century, had appeared in more than fifty Latin, Hebrew and vernacular editions and commentaries. It influenced students such as Nicolaus Copernicus (1473–1543), Galileo Galilei (1564–1642), and Johannes Kepler (1571–1630).

Peuerbach collaborated with his student and colleague Regiomontanus on a number of projects, including the observation of what came to be known as Halley's comet in 1456, and of a lunar eclipse on September 3, 1457, from a site near Vienna. At his death in 1461, he asked Regiomontanus to complete an abridgment of Ptolemy’s Almagest, in which he calculated tables of sines for every minute of arc for a radius of 600,000 units, and introduced the use of Hindu-Arabic numerals. He is credited with the invention of several scientific instruments, including the regula, the geometrical square. Peuerbach also served as a court astrologer for King Ladislaus V. Posthumus and, later, for Emperor Frederick III.

Life

Georg von Peuerbach was born Georg Aunpeckh at Peuerbach near Linz, sometime after 1421. His standard birthdate, May 30, 1423, is derived from a sixteenth-century horoscope. 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. He matriculated at the University of Vienna in 1446 and received his Bachelor of Arts in 1448.

From 1448 to 1450, he traveled in northern Italy. 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 lectured on astronomy in Padua, but refused offers of professorships at Bologna and Padua. He returned to Vienna, received his Master of Arts in 1453, and lectured on classical Latin poetry including Virgil and Juvenal. His scientific teaching was done chiefly in private, his most famous pupil being Johann Müller of Königsberg, later known as Regiomontanus.

Peuerbach’s acquaintance with Johann Nihil, astrologer of Emperor Frederick III of Hapsburg, and his reputation as a mathematician and astronomer, led to his association with several royal courts as astrologer. Among his first patrons was the emperor’s nephew, young King Ladislaus V. Posthumus, who ruled lower Austria, Bohemia and Hungary until his early death in 1457. Subsequently he served Emperor Frederick III, who held court in Wiener Neustadt, near Vienna.

At that time, the Austrian universities were very conservative and regarded the humanities with suspicion. At the court of Emperor Frederick III, the humanist Enea Silvio Piccolomini, (later Pope Pius II) gathered a group of early German humanists who studied the classical Latin writers and lived according to the urbane style. This group included Georg von Peuerbach and his student, Johannes Regiomontanus. Peuerbach’s Latin love poems and letters were considered to be in the best Latin style. Peuerbach was instrumental in bringing about a relationship between the natural sciences and the humanities. Together with his teacher, Johannes von Gmunden, and his student and colleague, Regiomontanus (J. Müller), Peuerbach established the first School of Mathematicians at the University of Vienna and made mathematics an ancillary science of astronomy.

Peuerbach collaborated with Regiomontanus on a number of projects, including the observation of what came to be known as Halley's comet in 1456, and of a lunar eclipse on September 3, 1457 from a site near Vienna. Peuerbach's best-known work, the Theoricae novae planetarum (1454; “New Theories of the Planets”), came from lectures which he gave to the Viennese “Citizens' School” (Bürgerschule), which Regiomontanus copied in his notebook. Peuerbach also computed an influential set of eclipse tables, Tabulae eclipsium (c. 1459), based on the thirteenth-century Alphonsine Tables, that circulated widely in manuscript before the first Viennese edition in 1514. In 1460, at the behest of Cardinal Johannes Bessarion, Peuerbach began an epitome, or abridgment, of Ptolemy's Almagest. Cardinal Bessarion invited him to come to Rome to study Ptolemy in the original Greek,instead of from a faulty Latin translation. Peuerbach accepted on the condition that Regiomonanus accompany him, but died in 1461 before the journey could be undertaken. At the time of his death, Peuerbach had finished only the first six (of thirteen) books; he asked Regiomontanus to completed the work (c. 1462), was was published in 1496 as Epytoma...in Almagestum Ptolomei.

The Purbach crater on the Moon is named after him.

Thought and Works

Peuerbach is considered a founder of observational and mathematical astronomy in the West. His work helped to pave the way for the Copernican conception of the world; he created a theory of planets, calculated tables of celestial eclipses, introduced the concept of the sine into trigonometry and invented a "quadratum geometricum" for measuring heights and distances.

In Epytoma...in Almagestum Ptolomei , the abridgment of Ptolemy's Almagest which was completed by his student, Regiomontanus, he replaced chords by sines, and calculated tables of sines for every minute of arc for a radius of 600,000 units. He made his observations with very simple instruments, using an ordinary plumb-line to measure the angles of elevation of the stars. He also introduced a mathematical innovation by using Hindu-Arabic numerals in his sine tables, the first transition from the duodecimal to the decimal system. Peuerbach noted several errors in Ptolemy’s calculations, but remained a devotee of the ancient Greek mathematician.

Peuerbach worked at the Observatory of Oradea/Nagyvarad in Transylvania and established in his "Tabula Varadiensis" that this Transylvanian town's observatory lay on the prime meridian of Earth. He is credited with the invention of several scientific instruments, including the regula, the geometrical square. Some attribute the "Jacob's Staff" to Peuerbach but this is an error, since the Jacob's Staff is kown to have been in use during the thirteenth century. [1].


Theoricae nova planetarum

Peuerbach's best-known work, the Theoricae novae planetarum (1454; “New Theories of the Planets”) discussed the epicycle theory of the planets first presented by Ptolemy. Peuerbach attempted to reconcile the opposing theories of the universe, the so-called homocentric spheres of Eudoxus of Cnidus and Aristotle, with Ptolemy's epicyclic trains, with an assertion that the planets revolve in transparent but solid spheres. In spite of this erroneous notion, his suggestion that the planets' movement is governed by the sun was an early step toward the refutation of the geocentric cosmology of Ptolemy. Peuerbach said little about the planetary spheres themselves, but the illustrations in the original manuscript and in first printed edition show eccentric planetary models embedded within spherical shells, with inner and outer surfaces concentric to the earth.

The first printed edition, in 1472, was the first product of Regiomontanus’ printing press in Nuremberg. Erhard Ratdolt included it in the elementary astronomical compendia he published in Venice 1482 and 1486, which were widely imitated. By the sixteenth century it had become an influential textbook of planetary theory, displacing the widely used, anonymous thirteenth-century Theorica planetarum communis (the common “Theory of the Planets”). By the late seventeenth century, Theoricae novae planetarum had appeared in more than fifty Latin, Hebrew and vernacular editions and commentaries. It introduced students such as Nicolaus Copernicus (1473–1543), Galileo Galilei (1564–1642), and Johannes Kepler (1571–1630) to an updated and simplified version of Ptolemy's Almagest that gave a physical interpretation to its mathematical models. Theoricæ remained the basis of academic instruction in astronomy until Copernicus’ theories became widely accepted.

Tabulae ecclipsium

Among Peuerbach's early astronomical works was Tabulae ecclipsium, which contained tables of his eclipse calculations. These were based on the thirteenth-century Alphonsine Tables, and employed innovative, labor-saving organization to ease computational difficulties. It circulated widely in manuscript before its first publication in Vienna in 1514. Peuerbach later published additional tables and developed several astronomical instruments for making observations, as well as a large star globe.

Works

Twenty of Peuerbach’s works are known; among these the following are the most important. Peuerbach composed other treatises, most still in manuscript, devoted to elementary arithmetic, sine tables, calculating devices, and the construction of astronomical instruments (gnomons, astrolabes, and quadrants).

  • 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).

References
ISBN links support NWE through referral fees

  • Glick, Thomas F., Steven John Livesey, and Faith Wallis. 2005. Medieval science, technology, and medicine: an encyclopedia. Routledge encyclopedias of the Middle Ages, 11. New York: Routledge. ISBN: 0415969301 9780415969307
  • Jaki, Stanley L. 1977. Planets and planetarians: a history of theories of the origin of planetary systems. New York: Wiley. ISBN: 0470991496 9780470991497
  • Rommel, Otto. 1947. Wiener Renaissance. Klassiker der Wiener Kultur, Bd. 1. Wien: Bellaria-Verlag.
  • Samhaber, Friedrich. 2000. Die Zeitzither: Georg von Peuerbach und das helle Mittelalter. [Raab]: Wambacher. ISBN: 3853600034 9783853600030
  • Strnadt, Julius. 1868. Peuerbach. Linz: [Druck von J. Wimmer].

External links

This article incorporates text from the public-domain Catholic Encyclopedia of 1913.

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