KEPLER’S LAW OF PLANETARY MOTION

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KEPLER’S LAW OF PLANETARY MOTION

1. First Law of Kepler (Law of Orbits)

Kepler’s First Law, also known as the Law of Orbits, states that every planet moves around the Sun in an elliptical orbit, with the Sun located at one focus of the ellipse. Before Kepler, scientists believed planetary orbits were perfect circles. However, Kepler showed that planets follow oval-shaped paths. The distance between a planet and the Sun changes continuously during its revolution. The point closest to the Sun is called perihelion, while the farthest point is called aphelion. This law provided a more accurate explanation of planetary motion and became a foundation for modern astronomy and celestial mechanics.

2. Second Law of Kepler (Law of Areas)

Kepler’s Second Law, known as the Law of Equal Areas, states that a line joining a planet and the Sun sweeps out equal areas in equal intervals of time. This means that planets do not move at a constant speed throughout their orbit. A planet travels faster when it is closer to the Sun and slower when it is farther away. Despite this variation in speed, the area swept by the imaginary line remains the same over equal time periods. This law explains the changing velocity of planets and helps astronomers accurately predict their positions in the solar system.

3. Third Law of Kepler (Law of Periods)

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