Erasmus Reinhold (October 22, 1511 – February 19, 1553) was a German astronomer and mathematician, considered to be the most influential astronomical pedagogue of his generation.
School period
College/University
Gallery of Erasmus Reinhold
Martin Luther University of Halle-Wittenberg, Halle, Saxony-Anhalt, Germany
Erasmus was educated, under Jacob Milich, at the University of Wittenberg, and his name is inscribed in the dean’s book for the winter term of 1530-1531.
Martin Luther University of Halle-Wittenberg, Halle, Saxony-Anhalt, Germany
Erasmus was educated, under Jacob Milich, at the University of Wittenberg, and his name is inscribed in the dean’s book for the winter term of 1530-1531.
Connections
colleague: Georg Joachim Rheticus
Georg Joachim Rheticus, Rheticus also spelled Rhäticus, or Rhetikus, original name Georg Joachim De Porris, or Von Lauchen, Austrian-born astronomer and mathematician who was among the first to adopt and spread the heliocentric theory of Nicolaus Copernicus.
teacher: Jacob Milich
Jacob (or Jakob) Milich (also Mühlich; January 24, 1501 – November 10, 1559) was a German mathematician, physician, and astronomer.
Primus secundus liber tabularum directionum. Discentibus prima elementa astronomiae necessarius & utilissimus. His insertus est Canon secundus ad singula scrupula quadrantis propagatus
Tabula declinationis eclipticae ad graduum dena scrupula extensa, qae maximam huius nostri seculi ex Tychonis Brahe accuratis observationibus tropicorum obliquitatem statuit graduum 23
Erasmus Reinhold was a German astronomer and mathematician. Reinhold was, after Copernicus, the leading mathematical astronomer of the sixteenth century. It is considered that in computational ability he surpassed even Copernicus himself.
Background
Erasmus Reinhold was born on October 22, 1511, in Saalfeld, Saxony. His father was Johann Reinhold (1479-1558), a tax collector and also the secretary of the last abbot of the Benedictine monastery at Saalfeld. Little is known about Erasmus's youth and early education. He had a brother, named Johann like their father, who became a professor of mathematics at Greifswald in 1549.
Education
Erasmus was educated, under Jacob Milich, at the University of Wittenberg. He studied mathematics under Jakob Milich (1501-1559) and graduated as Magister in 1535. His colleague, Georg Joachim Rheticus, also studied at Wittenberg and was appointed a professor of lower mathematics in 1536.
In May 1536 Philip Melanchthon appointed Erasmus professor of mathematum superiorum (astronomy) at the same time that Rheticus was named professor of lower mathematics. Reinhold was twice elected dean at Wittenberg: in the college of arts in the winter semester of 1540-1541 and in the college of philosophy in the summer semester of 1549. In the winter of 1549-1550, he became rector.
He fled from Wittenberg in 1552 in an attempt to escape the plague, but he died the following year in Saalfeld.
Cheap printed university textbooks first became popular in the 1540s, particularly at Wittenberg; and Reinhold published a widely reprinted commentary on Peuerbach’s Theoricae novae planetarum (1542) and one of the first book of Ptolemy's Almagest (1549). When Rheticus returned to Wittenberg in September 1541 from his visit to Copernicus.
Reinhold’s copy of Copernicus’ De revolutionibus is painstakingly annotated; it is virtually impossible to detect an error in the printed text not already marked by Reinhold. The pattern of annotations suggests that he was primarily interested in the model-building aspects of the work, especially in the way Copernicus had used combinations of circles to eliminate the Ptolemaic equant, and that he considered the heliocentric arrangement simply as a mathematical hypothesis of secondary interest.
Although Copernicus’ book includes tables as well as demonstrations, these were clumsy to use for calculations; and Reinhold, therefore, set out on “this huge and disagreeable task” (as Kepler called it) to cast them in a handier form. Already in January 1544, Reinhold wrote to his patron, Duke Albrecht of Prussia, about his intentions, but the actual work continued over many years and was interrupted by war in 1546-1547 when the university was closed. The resulting Prutenic Tables, named after both Copernicus and his patron, were finally printed in Tubingen in 1551; they rapidly became the most widely adopted astronomical tables. Reinhold systematically made small changes in the planetary parameters in order to have them conform more accurately with the observations recorded by Copernicus; he was apparently oblivious to the fact that this was an exercise in futility because of serious errors in the Copernican planetary positions. As for the arrangements of circles and epicyclets, Reinhold slavishly followed De revolutionibus, but the introduction to the tables, while praising Copernicus, was silent about the heliocentric cosmology.
The working manuscript in which Reinhold explored the effects of changing parameters on both the Ptolemaic and Copernican models still exists in Berlin. In 1957 A. Birkenmajer pointed out two short phrases which suggest that Reinhold had considered a proto-Tychonian arrangement of the planets, but this model was certainly not developed, and it is absent from other similar points in the manuscript. From hints in his printed works as well as in this manuscript, we can at best conclude that Reinhold did not ascribe physical reality to any particular planetary system.
Although Tycho Brahe never met Reinhold, the latter’s approach to Copernicus had a direct influence on the great Danish astronomer. Tycho came to Wittenberg on several occasions, and in 1575 he visited Reinhold’s son in Saalfeld; there he copied many of the annotations from Reinhold’s copy of De revolutionibus into his own. Reinhold’s notes emphasized Copernicus’ occasional uses of alternative arrangements of planetary circles, and it was in this framework that Tycho explored the various schemes that led to his own geocentric system.
The success of Reinhold’s Prutenic Tables enhanced Copernicus’ reputation, but his personal silence on the heliocentric world view fostered a pattern in astronomical lecturing at German universities that persisted for at least a generation after his own untimely death.
Quotations:
"Copernicus, the most learned man whom we are able to name other than Atlas and Ptolemy, even though he taught in a most learned manner the demonstrations and causes of motion based on observation, nevertheless fled from the job of constructing tables, so that if anyone computes from his tables, the computation is not even in agreement with his observations on which the foundation of the work rests. Therefore first I have compared the observations of Copernicus with those of Ptolemy and others as to which are the most accurate, but besides the bare observations, I have taken from Copernicus nothing other than traces of demonstrations. As for the tables of mean motion, and of prosthaphaereses and all the rest, I have constructed these anew, following absolutely no other reasoning than that which I have judged to be of maximum harmony."
Reinhold was one of the first to examine the new astronomy; and in the preface to his commentary on Peuerbach he wrote: “I know of a modern scientist who is exceptionally skillful. He has raised a lively expectancy in everybody. One hopes that he will restore astronomy,” and later, “I hope that this astronomer, whose genius all posterity will rightly admire, will at long last come to us from Prussia."
Personality
Quotes from others about the person
Kaspar Peucer, his successor at Wittenberg, wrote: "Of Erasmus Reinhold, my teacher, to whom I owe my eternal gratitude - a man well-versed not only in mathematics but in universal philosophy, and very careful besides - brilliant testimonies to this care exist and therefore his studies were correct and deserving the highest praise. He conceived of the greatest things, which he surely would have attacked and completed if a longer life had been granted him. Among others, he often promised us new hypotheses of motions, having grown weary of the Peuerbachians’. Unfortunately the other works that he was contemplating were impeded by the elaboration of the Prutenic Tables, which do exist, by their confirmation, which was somewhat weak, and by his premature death, which tore from us the fruits of his work that would have been handed down to posterity from his careful and unflagging study."
Connections
On 22 January 1537, he married Margareta Boner, daughter of a highly placed burgher in Saalfeld; she died in childbirth on 7 October 1548. In 1550 he re-married but he again lost his wife in childbirth. Erasmus was survived by two daughters, Margareta and Katharina, and by a son, Erasmus, who became a physician and issued a series of annual prognostications in the 1570s.