In Astronomy’s 2022 list of the 20 greatest astronomers of all time, Associate Editor Michael Bakich put Johannes Kepler, born Dec. 27, 1571, in Germany, at No. 3. He was ranked behind only his boss/collaborator, Tycho Brahe, at No. 2, and Galileo in the top slot.
Bakich noted: “Kepler’s importance to astronomy is so great that the final exam of my History of Astronomy course at Ohio State University consisted of just one question: Given Kepler’s laws of planetary motion, derive Newton’s three laws. Indeed, German astronomer Johannes Kepler’s laws — especially the first, which states that planets move in ellipses (not circles) — set the stage for the law of universal gravitation. In addition to many years of arduous orbital calculations, Kepler also observed a supernova, now called Kepler’s Nova, in 1604. Noting that the object showed no parallax, he concluded that it was neither atmospheric nor nearby, but that its distance must be the same as the other stars.”
