Page 2: Kepler's Laws and Geostationary Satellites

This page details the three laws of Kepler and the characteristics of satellite géostationnaire orbits, providing comprehensive explanations of planetary motion.

Definition: A geostationary satellite maintains a fixed position relative to Earth, with a revolution period matching Earth's rotation period of 23 hours and 56 minutes.

Highlight: Kepler's Three Laws are fundamental principles describing planetary motion:

1. 1ère loi de kepler: Planets move in elliptical orbits with the Sun at one focus
2. 2ème loi de kepler: A line joining a planet and the Sun sweeps out equal areas in equal times
3. 3ème loi de kepler: The square of the orbital period is proportional to the cube of the semi-major axis

Example: The varying speeds of planets in elliptical orbits are demonstrated, showing faster motion near perihelion (point B to C) compared to aphelion (point D to E).

Vocabulary:

• Semi-major axis: Half the longest diameter of an ellipse
• Perihelion: Point of closest approach to the Sun
• Aphelion: Point of furthest distance from the Sun