Copernicus, a great mind? Spare me! He made a total of 20 or so observations of the stars and planets; the rest, he took willy-nilly from minds greater than he, such as the ancient Greek astronomers, both geo- and helio-. He preferred the sun-worshipping helios. As for his claim that his epicycles were less than Ptolemy's, that is a lie. Ptolemy had only 40, Copernicus had 48. Copernicus lied about Ptolemy, saying Ptolemy's system had 80 eipcycles.