Kepler’s Laws of Planetary Motion The Law of Ellipses The Law of Equal Area The Law of Harmonies

Planets travel in an elliptical orbit with one focus being the sun. The Law of Ellipses Planets travel in an elliptical orbit with one focus being the sun.

Planets travel the same amount of area in the same amount of time in their orbits. The Law of Equal Area

The rate of revolution depends on distance from the sun. The Law of Harmonies The rate of revolution depends on distance from the sun.

How do celestial objects stay in orbit?

Inertia An object in motion tends to stay in motion An object at rest tends to stay at rest *unless acted upon by an outside force*

Gravity The force of gravity decreases with distance from center of gravity. When a planet is farthest from the sun there is less of a gravitational pull. This causes a planet to move slowest in it’s orbit when farthest from the sun.

Use Your ESRT p. 1

Eccentricity Eccentricity is measured on a scale of 0-1 The farther apart the foci, the higher the eccentricity

Eccentricity- How elongated an ellipse is Ellipse- A shape drawn using two foci Focus- A point on the major axis used to draw an ellipse (Plural-Foci) Major Axis- The longest line that goes through the center of the ellipse

Length of Major Axis- 15cm Distance between Foci-5cm Example Problem Length of Major Axis- 15cm Distance between Foci-5cm

Length of Major Axis- 17cm Distance between Foci- 7cm Example Problem Length of Major Axis- 17cm Distance between Foci- 7cm

Use Your ESRT p. 15

What is a planet’s favorite gum? Orbit