Cite
 

Meaning of Kepler's laws

Kep'ler's laws'

Pronunciation: [key]
— Astron. Astron.
  1. three laws governing planetary motion: each planet revolves in an ellipse, with the sun at one focus; the line connecting a planet to the sun sweeps out equal areas in equal periods of timethe square of the period of revolution of each planet is proportional to the cube of the semimajor axis of the planet's orbit
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.