Copernicus worked for years on his book describing his theory, and published it near the very end of his life. He entitled it, "De revolutionibus orbium coelestium" ("On the Revolutions of the Heavenly Spheres"), and published it in 1543. The major parts of Copernican theory are:
- Heavenly motions are uniform, eternal, and circular or compounded of several circles (epicycles).
- The center of the universe is near the Sun.
- Around the Sun, in order, are Mercury, Venus, Earth and Moon, Mars, Jupiter, Saturn, and the fixed stars.
- The Earth has three motions: daily rotation, annual revolution, and annual tilting of its axis.
- Retrograde motion of the planets is explained by the Earth's motion.
- The distance from the Earth to the sun is small compared to the distance to the stars.
The reception to his work was initially positive within the Catholic Church (contrary to popular belief, Galileo was not persecuted for supporting the Copernican theory, but because he was disrespectful to the Pope). However, the reaction was negative among Protestants who felt it conflicted with some literal interpretations of the Bible, such as the account of how Joshua benefited from the sun standing still as it passed over the earth. "And the sun stood still, and the moon stayed, until the people had avenged themselves upon their enemies. Is not this written in the book of Jasher? So the sun stood still in the midst of heaven, and hasted not to go down about a whole day." Joshua 10:13. But there were few Protestants in Poland then (or now), and Copernicus died without much controversy.