Kepler's law


Kep·​ler's law
: a statement in astronomy: the orbit of each planet is an ellipse that has the sun at one focus
: a statement in astronomy: the radius vector from the sun to each planet generates equal orbital areas in equal times
: 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

Word History


after Johannes Kepler

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Cite this Entry

“Kepler's law.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2023.

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