11/6/2014
Kepler’s Laws
This presentation will cover Kepler’s
1st and 2nd Laws only
Kepler’s 1st Law
Kepler’s 1st law states that all the planets move
in elliptical orbits, with the Sun at one foci of the
ellipse.
Earth
Sun
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11/6/2014
Kepler’s 2nd Law
Kepler’s 2nd law states an orbiting body sweeps out
equal areas in equal amounts of time. Because the
sectors you see were swept out in equal amounts of
time, their areas are equal.
Sun
Earth
Perihelion and Aphelion
In an elliptical orbit, planets move slowest when
they are farthest from the Sun and move fastest
when they are closest to the Sun.
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11/6/2014
Seasons with Relationship to Aphelion and
Perihelion
“Seasonal weather patterns are shaped primarily by the 23.5degree tilt of our planet's spin axis, not by Earth's elliptical orbit,”
explains George Lebo, a professor of astronomy at the University of
Florida.
T1 = T2 = T3 = T4 = ¼ of a year
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