Invited Talk - Plenary

Friday, 16 September 2022, 11:00   (Keksdose / virtual plenum)

Kepler & Olbers

Richard L. Kremer
Dartmouth College

Although separated by nearly two centuries, these two astronomers each solved a similar astronomical problem, viz., the computation of orbital trajectories from a limited number of positional measurements by using iteration and simplifying assumptions. Triangulating Mars’ orbit, Kepler in 1609 proposed that planets move in ellipses around the Sun. Accepting Newton’s view that comets move in parabolas past the Sun and assuming that these bodies move uniformly over short intervals, Olbers in the 1790s developed a simple procedure to determine their orbital elements. Throughout the 19th century, Olbers’ remained the standard method for determining cometary orbits. The Bremen city physician and the imperial mathematician are linked by their contributions to celestial mechanics.