Assignment #2 - The Copernican Revolution

Mikolaj Kopernik, or more well known as Nicolaus Copernicus, was a Polish astronomer and mathematician who lived from 1473-1543. He is well known for developing a heliocentric version of the solar system. However, the heliocentric model he is most known for was not particularly a new idea as others, like Aristarchus of Samos and Nicholas of Cusa, also proposed similar heliocentric theories but Copernicus was the one who developed mathematical backing to his theories. Copernicus targeted at establishing a few theories. First, that the Earth is spinning around its axis every day, while the immense distant world of stars is motionless. Second, the Earth is a planet orbiting the Sun once a year like the other planets, so it is not in the centre of the universe. Lastly, the Sun does not orbit around the Earth, but remains motionless in the centre of the planetary system.  

Copernicus was able to prove these theses through the means of observations over a long period of time. Within his book, he explains that the Earth must be rotating on its axis every 24 hours due to the movement of the stars in the sky around the Earth. Copernicus also observed that the other planets depicted the same orbit around the Sun that the Earth had shown. Although, Copernicus believed that these orbits were perfect circles (which was later disproven by Johannes Kepler). This furthered his belief of a heliocentric model against the Ptolemaic geocentric theory. Copernicus mainly used observations more than any mathematics or physics as his mathematical findings were used for the description of the planet’s motion.

Of the three theses, the last statement that the Sun does not orbit around the Earth, but rather remains motionless in the centre of the planetary system proved the most important to the field. Although Copernicus attempted to disprove the geocentric model with his heliocentric model, his model could not predict the positions of the planets any more accurately than the Ptolemaic model. In addition, the Copernican model’s inclusion of uniform circular motion was inaccurate. This meant that he established Earth as a planet but it also meant that all planets were treated as equal. By establishing the Sun at the centre of the universe and the Earth as a planet, it provided a stepping-stone that was used for many astronomers in the future. Through the observational work of Tycho Brahe and the mathematical genius of Johannes Kepler and Isaac Newton, Copernicus’ heliocentric model was transformed into the established ideas of our solar system in the present.

References:
http://csep10.phys.utk.edu/astr161/lect/retrograde/copernican.html
http://scienceworld.wolfram.com/biography/Copernicus.html