Synchronous orbit

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A satellite in synchronous orbit takes one day to complete one orbit, making the satellite return to the same point above the ground every day. If a satellite's inclination is 0 and the orbit is perfectly circular, it will appear stationary in the sky. If the inclination is nonzero and the orbit is non-circular, then the satellite will follow the path of a figure 8 about a central point on the equator.

For a satellite to maintain a synchronous orbit around Mars, set the orbital period of a satellite equal to one sidereal day.

T = 2 pi sqrt(a^3 / mu)


  • T = the orbital period, which is set to one sidereal day on Mars, 88642.66 s
  • mu = GM = the standard gravitational parameter, which is 4.282837e4 km3 s−2 for Mars
  • a is the semi-major axis of the orbit

Solving for a, we get

a = 20,427.7 km

For an Areostationary orbit, the radius will be 20,427.7 km and the inclination will be zero.