Reinhold, E
NAME: Reinhold, Erasmus
ACHIEVEMENT(S): After Copernicus, the leading mathematical astronomer of the sixteenth century.
NICKNAME/ALIAS: None.
DATE/PLACE OF BIRTH: 22ndOctober 1511, at Saalfeld, Germany.
DATE/PLACE/AGE AT DEATH: 19th February 1553, in Saalfeld, Germany. Aged 42.
DISCIPLINE: Astronomer.
FIELD: Astronomy.
LANGUAGE: German.
PARENTS: Johann Reinhold and ?
SIBLINGS: Johann.
SPOUSE: Margarete Boner, married 1537-48, married second wife 1550-52.
CHILDREN: Margarete, Katharina and Erasmus.
EDUCATION: University of Wittenberg
MAJOR WORK: 'Prutenic Tables', 1551.
LIFE AND TIMES: Reinhold enrolled at the University of Wittenberg in 1530 and in May 1536, Melanchthon* gave him the job of Professor of Astronomy, at the same time that he made the Austrian Rheticus*, Professor of Mathematics.
On 22ndJanuary 1537, Reinhold married Margareta Boner, the daughter of a burgher in Saalfeld, who bore three children. In 1540, he was elected Dean of the College of Arts at Wittenberg and, in September of the following year, Rheticus returned from visiting Copernicus* bringing a manuscript copy of 'De Revolutionibus'.
When he got hold of his own copy, Reinhold became one of the first to study the new astronomy, and his copy of 'De Revolutionibus' is heavily annotated.
The notes showed that he was interested in the way Copernicus had used combinations of circles to eliminate the Ptolemaic equant, an imaginary point in space introduced by Ptolemy* to account for observed variations in planetary orbital velocity. It was apparent from his notes that Reinhold considered the heliocentric system as purely a mathematical hypothesis and of only secondary interest.
In 1542, he published a commentary on Peuerbach's* century-old 'Theoricae Novae Planetarum.' A commentary on the first book of Ptolemy's 'Almagest' followed in 1549. He continued to study 'De Revolutionibus', and wrote a commentary on it.
Copernicus's work contained tables as well as demonstrations, but they were difficult to use, so Reinhold reworked them and published his own 'Prutenic Tables', printed in Tubingen in 1551 and dedicated to the ruler of Prussia. The tables ignored the question of heliocentric cosmology, but were more accurate and up-to-date than the 13th-century model, and because of their accuracy were quickly adopted by both astronomers and astrologers.
Reinhold did not fully accept the heliocentric theory and may himself have invented something resembling the Tychonic theory before Brahe* himself, proposing a modified Copernican system in which the planets revolved around the sun which in turn moved around the stationary earth. Reinhold’s notes greatly influenced Tycho when he developed his own geocentric system.
He became Dean of the College of Philosophy in the summer of 1549, and, in the winter of 1549-50, he became Rector. Two years later, in an attempt to escape the plague, he left Wittenberg and went to Saalfeld, where he died the following year.
Reinhold’s 'Prutenic Tables' were reprinted many times, most notably in 1571, when they were re-published with a brief appendix by the twenty-one-year-old astronomer Maestlin*.
ASSESSMENT: Reinhold's 'Prutenic Tables' became the most popular astronomical tables of the 16th century.
EXTRA CONNECTIONS: None.
ONELINER: Erasmus Reinhold, second-best 16th-century astronomer after Copernicus
BIBLIOGRAPHY:
Walker, Christopher, Astronomy before the Telescope, London: British Museum Press, 1996.