An astronomer who faced the facts and revolutionized our view of the universe, Nicolaus Copernicus (1473-1543) was born on this day into a wealthy family in Torun, Poland.

Folllowing the death of his father, he was supported by his maternal uncle, a Catholic bishop, and studied science at the University of Bologna.

He once said: "To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge."

With a passion for astronomy and mathematics, he began gathering ideas about the universe in 1504. "Mathematics is written for mathematicians," he said.

By 1507, he circulated the handwritten Commentariolus, his heliocentric model, with the sun, not earth, in the center of the solar system. "We shall place the Sun himself at the center of the Universe," he said. "All this is suggested by the systematic procession of events and the harmony of the whole Universe."

Addressing himself to "this very difficult and almost insoluble problem," Copernicus questioned the views of earth established by Aristotle and Ptolemy and spent 16 years refining his theory. His masterpiece, De Revolutionibus, offered evidence for the heliocentric model and was published the year of his death.

The ideological revolution began...

Facts do not cease to exist because they are ignored.