On February 19, 1473, astronomer Nicolaus Copernicus [Mikołaj Kopernik] was born in Prussia [present day Poland]. He studied mathematics, optics, and canon or church law. Thanks to an interested and protective uncle, Copernicus was appointed a canon to the Frauenburg cathedral where he spent most of the remainder of his life.
In his day, the established view of celestial movement was that the sun and stars orbited the Earth. For Copernicus, like several others who questioned it, this old theory of orbital mechanics left too many things unexplained. He reasoned that if one could accept that the sun was the body that remained in position and it was the Earth that moved around, the movement of the other planets could be explained. Copernicus was certain that this heliocentric or sun-centred theory of the solar system represented the real world.
When he tested his observations against his theory, Copernicus found he could determine the order of the visible planets, including the Earth, in their distance from the sun. This also signalled to him that the movement of the Earth could account for the apparent daily movement of the stars.
Within this heliocentric system, Copernicus could reckon the approximate length of time, in Earth days, of the sidereal period or the time taken for each planet to complete one orbit about the sun. Since it took the Earth a year to complete its solar orbit, the length of its journey could also account for the seasonal changes and equinox sequence. Copernicus further realized that the Earth rotated on its own axis and that rotation took a day to complete.
Although he did not have the technology to prove his theory, Copernicus compiled his life’s work and the reasons for his heliocentric theory in De Revolutionibus Orbium Coelestium, “On the Revolutions of the Celestial Spheres” in Latin. Published and circulated through several editions, heliocentric theory was out into the world – an invitation for future astronomers and mathematicians to test, modify, and build upon.
B Bondar / Real World Content Advantage