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Johannes Kepler

1571–1630 · Astronomy, Mathematics, Optics
German astronomer, mathematician, and optician, who discovered the laws of planetary motion named after him. He showed that planets move in elliptical orbits with variable speed, and established a mathematical relationship between the orbital period and the distance from the Sun. His work became the foundation for Newton's theory of gravity. He also contributed to optics and stereometry.

Biography

Born in Weil der Stadt. Studied at the University of Tübingen, where he became a supporter of Copernicus' teachings. Worked as an assistant to Tycho Brahe, after his death inherited the most precise astronomical observations. Imperial mathematician in Prague under Rudolf II. Author of books 'New Astronomy', 'Harmonices Mundi'.

Key discoveries

💡 Kepler believed in the 'music of the spheres' and sought harmonic relationships between the orbits of the planets, trying to fit them into a system of polyhedra.
"He said that he wrote a book so that it would be read by contemporaries or descendants, and that it doesn't matter, as it can wait hundreds of years for its reader, just as God waited six thousand years to see his spectator."
Concepts
gravitysupernova
Laws
Kepler's third lawKepler's first lawKepler's second lawNewton's second lawlaw of conservation of angular momentum
Scientists
Robert HookeJacob BekensteinKarl SchwarzschildJoseph WeberFred HoyleAdam RiessBrian SchmidtNicolaus Copernicus

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