Nicolaus Copernicus was born on February 19, 1473. He was an official of the cathedral of Frombork (in present day Poland) and prominent citizen of that town. In fact, his astronomy had to be a minor activity with all of his other responsibilities.
He had discussed his ideas about the Earth and other planets revolving around the Sun, instead of everything going around the Earth. It helped to explain some things that didn't work with an Earth-centered view. However it was a long time before the idea was accepted by most astronomers. You can find out
by clicking here why the idea was revolutionary at the time. His major work explaining the theory was published on the day he died.
Last year he got an animated doodle from Google showing a model of the Copernican theory. Here is a
link to a You Tube animation of the doodle.