1. Kepler’s Laws
Of Planetary Motions

2. Who was the man? 7th Century: 1571-1630
German mathematician, astronomer, and astrologer
Best known for his laws of planetary motion
Assistant of Tycho Brahe

3. Introduction
Kepler derived the laws from Tycho Brahe’s extensive observations.
Astronomer
Didn’t use a telescope
Known for accurate and comprehensive astronomical and planetary observations
Kepler’s three laws are empirical
describe a phenomenon without explaining why it occurs.

4. Kepler’s first law
Kepler was able to recognize the elliptical shape of the orbits.
Kepler’s first law states that the orbits of the planets around the sun are ellipses with the sun at one focus.

5. Ellipse
An ellipse is a figure that is drawn around two points called the foci (pivot points).
Drawn in such a way that the distance from one focus to any point on the ellipse and back to the other focus is constant no matter where you look
The ellipse was the key to the solution of how planets move.
Each planet has a specific ellipse orbit

6. Ellipse

7. Kepler’s second Law
States that as planets orbit the sun their path sweeps over equal areas in equal intervals of time.
When planets are closer to the sun = move more rapidly
When planets are further from sun = move slower

9. Support Videos