Kepler’s second law

Definition

Kepler’s second law states that a line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. This implies that planets move faster when they are closer to the Sun and slower when they are farther from the Sun.

5 Must Know Facts For Your Next Test

1. Kepler's second law is also known as the Law of Equal Areas.
2. It indicates that planetary orbits are elliptical, not circular.
3. The speed of a planet in its orbit varies depending on its distance from the Sun.
4. This law helps explain why planets have varying orbital velocities.
5. Kepler's second law is essential for understanding orbital mechanics and predicting planetary positions.

Review Questions

• What does Kepler’s second law state about the areas swept by a planet in its orbit?
• How does Kepler’s second law affect the speed of a planet at different points in its orbit?
• Why is Kepler’s second law important for understanding planetary motion?

Related terms

Kepler's First Law: States that planets move in elliptical orbits with the Sun at one focus.

Kepler's Third Law:

Describes the relationship between a planet's orbital period and its average distance from the Sun.

Elliptical Orbit:

An oval-shaped path followed by planets around the Sun, characterized by varying distances from the focal point.