Nicolaus Copernicus

Nicolaus Copernicus (Polish name: Mikołaj Kopernik) was a fifteenth century astronomer and founder of the heliocentric system, i.e., a planetary system with the sun and not the earth as center of the system. Nicolaus was born in Toruń on 19 Februari 1473 and died in Frombork on 24 May 1543. The cities of birth and death of Copernicus are now Polish, but were German speaking during the days of Copernicus with the respective German names Thorn en Frauenburg. For the largest part of his life Copernicus worked and lived in Frombork, in the East of Poland at the Baltic Sea. This city is the seat of the diocese Warnia (in German Ermland). Although Copernicus was not ordained, he made his living as canon of this diocese and lived the life of a Roman Catholic priest.

At an early age Nicolaus showed much affection for astronomy, yet he made the sensible choice of studying law and medicine, two professions that obviously gave him a greater chance of finding a decent job than astronomy would. After three years of study (1491–1494), he received a bachelor's degree at the Jagiellonian University in Cracow and got two master's degrees in Italy, one in Bologna and one in Padua. Copernicus stayed in Italy from 1496 until about 1503. He received a doctorate in canonical law at the university of Ferrara in 1503.

Probably Copernicus, while in Italy, got acquainted with the heliocentric model of Aristarchus (ca. 310–230 BC). There is an early (1514) manuscript of Copernicus in which he posits that the earth orbits around the sun in one year time and that the retrograde motions of th eplanets are only apparent, that is, are caused by obseravtion from a moving earth.