Kepler's law

Kep·​ler's law | \ ˈkeplə(r)z- \

Definition of Kepler's law

1 : a statement in astronomy: the orbit of each planet is an ellipse that has the sun at one focus
2 : a statement in astronomy: the radius vector from the sun to each planet generates equal orbital areas in equal times
3 : a statement in astronomy: the ratio of the square of the revolution period to the cube of the orbital major axis is the same for all the planets

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History and Etymology for Kepler's law

after Johannes Kepler

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Kepler's law

Keplerian telescope

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Cite this Entry

“Kepler's law.” Dictionary, Merriam-Webster, Accessed 7 Aug. 2022.

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