CIE A Level Physics复习笔记13.1.4 Geostationary Orbits

• Many communication satellites around Earth follow a geostationary orbit
• This is a specific type of orbit in which the satellite:
  • Remains directly above the equator, therefore, it always orbits at the same point above the Earth’s surface
  • Moves from west to east (same direction as the Earth spins)
  • Has an orbital time period equal to Earth’s rotational period of 24 hours

• Geostationary satellites are used for telecommunication transmissions (e.g. radio) and television broadcast
• A base station on Earth sends the TV signal up to the satellite where it is amplified and broadcast back to the ground to the desired locations
• The satellite receiver dishes on the surface must point towards the same point in the sky
  • Since the geostationary orbits of the satellites are fixed, the receiver dishes can be fixed too

Geostationary satellite in orbit