Erasmus Reinhold

Erasmus Reinhold, born on October twenty-second, fifteen eleven, in Saalfeld, Saxony, was a prominent German mathematician and astronomer. Renowned as the most influential astronomical pedagogue of his generation, he made significant contributions to the field of mathematics, which during his time encompassed applied mathematics, particularly astronomy.

Reinhold's academic journey began at the University of Wittenberg, where he studied under Jacob Milich. His leadership qualities soon shone through as he was elected dean and later became rector. In fifteen thirty-six, he was appointed professor of higher mathematics by the esteemed Philipp Melanchthon. His colleague, Georg Joachim Rheticus, also emerged from Wittenberg, taking on the role of professor of lower mathematics in the same year.

Among his notable achievements, Reinhold catalogued a vast number of stars and published significant works on astronomy, including a commentary on Georg Purbach's Theoricae novae planetarum in fifteen forty-two and fifteen fifty-three. He was aware of Copernicus and his heliocentric theories before the release of De revolutionibus, and he acknowledged Copernicus favorably in his commentary, although he ultimately rejected heliocentric cosmology in favor of a geocentric system.

Supported by Duke Albert of Brandenburg Prussia, Reinhold's Prutenicae Tabulae, published in fifteen fifty-one, fifteen sixty-two, fifteen seventy-one, and fifteen eighty-five, played a crucial role in disseminating Copernican calculation methods throughout the Empire. Despite their significance, these tables exhibited a notable lack of commitment to heliocentricity. Reinhold's work laid the groundwork for the Calendar Reform initiated by Pope Gregory XIII in fifteen eighty-two.

His heavily annotated copy of De revolutionibus, housed in the Royal Observatory in Edinburgh, sparked Owen Gingerich's quest for early editions of the work. In his unpublished commentary, Reinhold calculated the distance from the Earth to the Sun, adjusting his methods to align closely with Ptolemy's findings. His legacy is further immortalized by a lunar impact crater named in his honor, located south-southwest of Copernicus on the Mare Insularum.