Today in the history of astronomy, the astronomer responsible for the laws of planetary motion is born.
Johannes Kepler left a legacy in astronomy, scientific method, physics, and much more that truly influenced all science work that came after him. Credit: August Köhler, Public Domain via Wikimedia Commons
- Johannes Kepler was ranked third in *Astronomy*’s 2022 list of the 20 Greatest Astronomers, behind Tycho Brahe and Galileo.
- Kepler’s laws of planetary motion, especially the first law to posit elliptical orbits, were important in establishing the outline of the law of universal gravitation.
- His profound influence on astronomy is demonstrated by an academic exercise requiring the derivation of Newton’s three laws from Kepler’s laws.
- Kepler’s observations of the 1604 supernova (Kepler’s nova) led him to conclude its stellar distance based on the absence of observable parallax.
In AstronomyIn a 2022 list of the 20 greatest astronomers of all time, Associate Editor Michael Bakich ranked Johannes Kepler, born December 27, 1571, in Germany, at No. 3. He was behind only his boss/collaborator Tycho Brahe, who was ranked No. 2, and Galileo took the top spot.
Bakich said: “Kepler’s importance to astronomy is so great that the final exam for my history of astronomy course at Ohio State University included just one question: Given Kepler’s laws of planetary motion, derive Newton’s three laws. In fact, the German astronomer Johannes Kepler’s laws – especially the first, which states that the planets move in ellipses (not circles) – set the stage for the law of universal gravitation. Several years apart, it was difficult. Following 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 should be similar to that of other stars.
