Regiomontanus
Nickname/Alias: Johann Muller; Johannes de Monteregio; Joannes Germanus; Francus
Achievements: Responsible for the revival and advancement of trigonometry in Europe.
Born: June 6, 1436; Konigsberg, Franconia, Germany (now Kaliningrad, Russia)
Died: July 6, 1476; Rome, Italy; (Aged 40)
Field & Discipline: Science; Matematics; Astronomy; Trigonometry
Language: German
Father: Unknown
Mother: Unknown
Siblings: Unknown
Spouse: Unknown
Children: Unknown
Education: University of Leipzig (1447-50); University of Vienna (1450-52)
Major Work:
“Epitome of the Almagest” (1496, with Peuerbach)
Life & Times:
As a child prodigy, at the age of 12 Regiomontanus computed a daily table for the positions of the sun, moon and planets for the year 1448.
In 1450, he went to Vienna to be close to the astronomer [collaborated with] Peuerbach* and matriculated there as Johannes Molitoris de Kunigsperg. Later, he translated his name into Latin, Regiomonte, which became standardized as Regiomontanus. He won his Master's in 1457 and became a lecturer, working with Peuerbach.
Over the next few years, they worked together on many occasions, revealing the inaccuracies in the Alfonsine Tables, and the Latin translations of the Greek astronomers from intermediate Arabic translations. Together they observed what is now known as Halley's Comet, in June 1456 and on September 3, 1457, they observed a lunar eclipse eight minutes earlier than predicted by the existing tables.
In 1459, Peuerbach produced his own set of tables and in 1460 Regiomontanus joined him to observe lunar eclipses on 3rd ^July and 27thand 28thDecember, this time comparing the observations with Peuerbach's tables.
Their results were not published until 1544, but from his observations Peuerbach was able to determine the latitude of 48 degrees 22 minutes for Vienna (the correct latitude being 48 degrees 13 minutes).
On May 5, 1460, the Archbishop of Nicaea, [commissioned by] Bessarion*, came to Vienna to try to enlist the help of Emperor Friedrich III against the Turks who were occupying Constantinople. A student of Gemistus Pletho, Bessarion had previously begun a translation of Ptolemy's “Almagest,” to replace the translation by Gerard of Cremona.
Bessarion wanted an abridged version of the “Almagest” and arranged for it to be done by Peuerbach and Regiomontanus. With only six books completed, Peuerbach became ill in April 1461, and, before his death, asked Regiomontanus to carry on the work. He agreed and, on November 20, 1461, in the company of Bessarion, arrived in Rome where he studied Greek (to help with the abridgement) and over the next year finished seven more books to complete the work.
In 1463 he dedicated the finished “Epitome of the Almagest” to Bessarion. The “Epitome” was much more that an abridgement of the “Almagest.” Regiomontanus reworked Ptolemy's tables, creating a work of much greater clarity, and giving Western scholars a more accurate guide to Ptolemy's mathematical techniques.
Influenced by Regiomontanus’ correction of an error in Ptolemy's astronomical system (unquestioned for over 1,300 years) [influenced] Copernicus* went on to lay the foundations of modern astronomy.
In the summer of 1463, Bessarion and Regiomontanus left Rome for Venice. The following year, Regiomontanus lectured at the University of Padua on the 9thcentury scientist [lectured on] Al-Farghani* and spent time revising John of Seville's Latin translation of Al-Farghani's “Elements of Astronomy.”
At the same time, he revised and added geometrical proofs to [improved work of] Plato of Tivoli*'s 12thcentury version of [improved work of] Al-Battani's* “The Motions of the Stars,” the two Islamic works being published together in 1573, with Regiomontanus' additions and annotations.
In August 1464, Regiomontanus went to Rome with Bessarion. In 1463 he had begun a basic work on trigonometry, “On Triangles of Every Kind,” and in Rome he extended the work to “Five Books on Triangles of All Kinds.” Finally printed in 1533, this work had a huge impact on the later development of trigonometry.
From 1465 to 1467, Regiomontanus travelled around northern Italy, meeting other mathematicians and astronomers and continuing his observations. In 1467 he was given the job of royal librarian at the Hungarian court, where his main task was collating the king's many Greek manuscripts.
In 1471 Regiomontanus left Hungary and settled in Nuremberg, Germany, where a new patron, the wealthy Bernhard Walther, had offered him a house, a tool shop, an observatory and a printing press. He also began teaching, and the geographer [taught] Behaim* later claimed he was one of Regiomontanus’ pupils.
In Nuremberg, Regiomontanus became the first publisher of astronomical and mathematical literature, providing scientists with clear texts, aided by his design of a simple, clear German typeface, and the introduction of the Latin alphabet into printing for the first time.
Regiomontanus' first publications included his navigational tables, the “Ephemerides,” which appeared in 1474, predicted eclipse dates from 1475 to 1506, and was taken by [work used by] Columbus* on his fourth voyage, when he used its prediction of the lunar eclipse of 29thFebruary 1504 to frighten the hostile natives in Jamaica into submission.
Regiomontanus also improved sighting instruments like the Jacob's staff, the triquetrum and the quadrant, which he and Walther used to establish more accurate data on solar altitudes and planetary and stellar positions. A century later the astronomers [work used by] Brahe* and [work used by] Kepler* made use of the Regiomontanus-Walther data.
In 1475, Pope Sixtus IV called Regiomontanus to Rome, made him Bishop of Regensburg and gave him the job of reforming the Julian calendar. However, Rgiomontanus died before he could begin the work.
Extra Connections:[biography written by] Gassendi* wrote his biography.
Influenced by [influenced by] ben Gershom*, and [influenced by] Witelo*
He admired [admired work of] Toscanelli*’s mathematics
Assessment: His abridgement of the “Almagest” with Peuerbach was a major astronomical advance.
Oneliner: Regiomontanus, Renaissance trigonometry expert
Bibliography:
- O'Neil, W.M., Early Astronomy from Babylonia to Copernicus, Sydney University Press, 1989.
- Zinner, E., Regiomontanus: His Life and Work, Amsterdam, 1990.