Who was Copernicus?
Nicolaus Copernicus was a Polish astronomer who was best known for a new theory that he propounded. He was the first scientist to suggest that the sun was at rest near the centre of the universe and that the earth, while continuing to spin on its axis daily, revolved around the Sun annually. The system came to be known the heliocentric or sun-centered system.

Copernicus

His life history
Copernicus was born into a family of merchants in Poland, on February 19, 1473. After his father’s death in 1483, his uncle, Bishop Watzenrode, brought him up. Extremely fond of his nephew, his uncle ensured that Copernicus got a good education at the best of universities. Copernicus first studied arts for four years and without obtaining a degree left for Italy to study medicine and law.    

The turning point in his life came in early 1497, when he began studying canon law at the University of Bologna. He was living in the home of a mathematics professor, Domenico Maria de Novara, who questioned the theories of the second century astronomer, Ptolemy. Copernicus was drawn by his host’s deep knowledge of geography and astronomy. In the company of Domenico Maria, Copernicus observed the occultation (the eclipse by the moon) of the star Aldebaran on March 9, 1497.    

One of Copernicus’ early brushes with astronomy was a lecture that he delivered in Rome in 1500. He then joined the university at Padua to take up the study of medicine, obtained a doctorate in canon law and returned to Poland, where he took up a job as desired by his uncle. The job was that of a church administrator with financial responsibilities but no priestly duties.

Back in Poland, between the years 1507 and 1515, Copernicus wrote a small treatise known as the Commentariolus, in which he laid down the principles of his new heliocentric astronomy. His major work, On the Revolutions of the Celestial Spheres, which was completed by the year 1530 but was published only before his death in 1543.

The Copernicus theory
The theory put forward by Copernicus was that the earth rotates daily on its axis and revolves annually around the Sun. It wobbles like a top as it rotates, Copernicus had stated. Prior to this, it was thought that the earth was stationary and that it was motionless at the centre of several concentric, rotating spheres. It was these spheres that bore the moon and the other five planets (Pluto and the Earth, of course, being excluded). All fixed stars were borne by the finite outermost sphere. It was Copernicus’ belief that the planets also revolve around the Sun.

The theory that he propounded provided an explanation for the motion of the planets, sun, moon and the stars. Based on the time duration of the revolution of each planet, the Copernicus theory allowed for a new order for the locations of the planets.  

As it happens with anything that is new and revolutionary, Copernicus’ theory too was rejected by many. Those that understood it said that it was neither decisively simple nor accurate in calculation to justify a replacement of the earlier theories. However, it was partially accepted, since it did explain several hitherto unexplained phenomena in science. 

Among those that supported Copernicus were the famous astronomers Galileo and Johannes Kepler, an expert from Germany. In the meantime, in the year 1588, a Danish astronomer Tycho Brahe propounded a theory that whereas the earth remained stationary, the planets revolved around the Sun as it revolved around the earth. It was only in the late seventeenth century that the Copernican theory began to be accepted. Many still preferred Brahe’s theory to Copernicus’. However, by the end of the eighteenth century, the Copernicus theory came to be accepted by scholars in the scientific community.