Copernicus was a church canon, physician, and economist, but his most important work was in the field of astronomy. He developed the heliocentric theory of the universe that placed the Sun, not the Earth, at the center of our solar system and helped launch a scientific revolution. Though Copernicus conceived his revolutionary model of planetary motion by 1530, his treatise on the subject did not see print until he was on his deathbed in 1543. What heliocentric hypotheses preceded Copernicus’s? Discuss
Source: The Free Dictionary