Kepler's law

American  

noun

Astronomy.

1. any one of 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 time law of areas; or the square of the period of revolution of each planet is proportional to the cube of the semimajor axis of the planet's orbit harmonic law.

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Etymology

Origin of Kepler's law

After J. Kepler

Example Sentences

The masses are found using Kepler’s law for those few pulsars that are members of binary star systems.

From Textbooks • Oct. 13, 2016

By Kepler’s law, the planet moves fastest in its orbit when closest to the Sun.

From Textbooks • Oct. 13, 2016

From Kepler’s law, the period and the separation allow us to calculate the sum of the stars’ masses.

From Textbooks • Oct. 13, 2016

Newton proved Kepler’s law using his second law of motion and his law of universal gravitation.

From Textbooks • Mar. 30, 2016

But it no more disturbs the fundamental truth of the Principle of Sincerity, than the perturbations in the orbit of Mars disturb the truth of Kepler's law.

From The Principles of Success in Literature by Lewes, George Henry