Kepler's law

noun

Kep·​ler's law

ˈkeplə(r)z-

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

Word History

Etymology

after Johannes Kepler

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