In astronomy, Kepler's laws of planetary motion are three scientific laws describing orbital motion, each giving a description of the motion of planets around the Sun.
Kepler's laws are:
- The orbit of every planet is an ellipse with the Sun at one of the two foci.
- A line joining a planet and the Sun sweeps out equal areas during equal intervals of time.
- The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.
Read more about Kepler's Laws Of Planetary Motion: History, First Law, Second Law, Third Law, Generality, Zero Eccentricity, Relation To Newton's Laws, Computing Position As A Function of Time, Computing The Planetary Acceleration, Newton's Law of Gravitation
Famous quotes containing the words laws, planetary and/or motion:
“Those rules of old discovered, not devised,
Are Nature sill, but Nature methodized;
Nature, like liberty, is but restrained
By the same laws which first herself ordained.”
—Alexander Pope (1688–1744)
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“in the mind of man,
A motion and a spirit, that impels
All thinking things, all objects of all thought,
And rolls through all things.”
—William Wordsworth (1770–1850)