Angelus (Engel), Johannes

(b. Aichach, Germany, 2 March 1453 [?]; d. Vienna, Austria, 29 September 1512)

astronomy.

Although Angelus has been mentioned by many competent authors, reliable information about his life is scarce. From a few fairly certain dates the following sketch may be drawn.

In 1468 Angelus began his studies at the University of Vienna as a pupil of the famous astronomer Regiomontanus. In January 1471 he received the baccalaureate and most probably continued his studies in Italy. After having received the master’s degree in liberal arts and the doctorate in medicine, Angelus returned to Bavaria, where he subsisted by practicing medicine and astrology in Augsburg. There, in 1489, he published his Ephemerides—astronomical predictions of the phases of the moon, eclipses, and planetary phenomena—based on Regiomontanus’ improved tables. In the same year he published a revised translation of Abū Ma‘shar’s eight–volume work De magnis conjunctionibus, for speculations on the allerged effects of conjunctions of Jupiter with Saturn were then in vogue. Angelus also wrote a treatise on calendar reform and many astrological prognostica.

Apparently in Italy again about 1494, Angelus published an astrological volume containing two treatises, “Astrolabium planum” and “De nativitatibus.” In the same year he was made a member of the Faculty of Liberal Arts at the University of Vienna, where he spent the rest of his life improving Peuerbach’s planetary tables. Even if he had succeeded in accomplishing this work before his death, it would not essentially have influenced the subsequent development of astronomy, since at nearly the same time Copernicus wrote his first Commentariolus on the heliocentric system. But, according to Tannstetter, among his contemporaries Angelus was esteemed as an “excellent astronomer.”

BIBLIOGRAPHY

1. Original Works. Angelus writings are Albumazaris de magnis conjuncationibus (Augsburg, 1489); Ephemerides (Augsburg, 1489); and a volume containing “Astrolabium planum cum aequationibus domorum coeli” and “Tractatus de nativitatibus” (Venice, 1494).

II. Secondary Litrature. A short, firsthand report is given by George Tannstetter in the introduction to his ed. of Tabulae eclypsium magistri Gergij Peurbachij (Vienna, 1514). See also Carl Bruhns, “Johann Angelus,” in Neue deutsche Biographie, I (1875), 457; Christian Gottlieb Jöcher in Allgemeines Gelehrten–Lexikon, I (1750), 415; and Poggendorff, 1, 47, 1528.

Konradin Ferrari D’Occhieppo