Geostationary Orbits

• What is a synchronous orbit?

  Orbiting body has the same period as the orbited body
• How does a synchronous orbit relate to satellites?

  It usually refers to satellites around planets
• What is a geosynchronous orbit?

  Orbit directly above the equator
• What is the significance of a geostationary orbit?

  Satellite remains above the same point on Earth
• What direction do geostationary satellites move?

  From west to east
• What is the orbital period of a geostationary satellite?

  24 hours
• What are geostationary satellites used for?

  Telecommunication transmissions and television broadcasts
• How does a base station communicate with a geostationary satellite?

  It sends signals to the satellite for broadcasting

  
• What must satellite receiver dishes do in relation to geostationary satellites?

  Point towards the same point in the sky
• Why can receiver dishes be fixed for geostationary satellites?

  Because the orbits of the satellites are fixed
• What characterizes low orbits for satellites?

  Altitude is closer to the Earth's surface
• What is a polar orbit?

  Satellite orbits around the north and south poles
• What are low orbits useful for?

  Taking high-quality photographs of Earth's surface
• What is the period of a low-Earth orbit (LEO) satellite?

  89 minutes
• What is the height of a low-Earth orbit (LEO) satellite?

  250 km
• What is the orbital period of a geostationary satellite in minutes?

  1440 minutes
• How do you calculate the height of a geostationary satellite?

  Using the relationship between orbital period and radius
• What is the relationship between orbital period and radius?

  Orbital period T is related to radius r by $T^2 \propto r^3$
• What is the formula to find the orbital radius of a geostationary satellite?

  $r_G =$$r_L \left(\frac{T_G}{T_L}\right)^{\frac{2}{3}}$
• What is the final height above the Earth's surface for a geostationary satellite?

  36,000 km
• What are the key features of a geostationary orbit?

  • Equatorial orbit
  • Moves west to east
  • Period of 24 hours
• What should you memorize for geostationary orbit questions?

  • Key features of geostationary orbit
  • Time period of 24 hours for calculations