A Geosynchronous orbit is typically characterized by which shape?

A Geosynchronous orbit is typically characterized by which shape?

• A. Elliptical
• B. Parabolic
• C. Circular
• D. Hyperbolic

Answer: (C)

Geosynchronous means the satellite’s orbital period matches the Earth’s rotation, so it completes one orbit in about 24 hours. The simplest way to achieve a 24-hour period with a stable, constant distance from Earth is a circular orbit. In a circular orbit, the radius stays fixed and the speed is constant, so the satellite can, in the right plane (often the equatorial plane), stay over roughly the same longitude relative to the surface. This is why a circular shape is the typical description for geosynchronous orbits. Elliptical orbits can be tuned to have a 24-hour period as well, but the distance to Earth then varies during each orbit, causing the satellite’s ground track to move rather than stay fixed. Parabolic and hyperbolic shapes are unbound trajectories and don’t sustain a long-term orbit around Earth.

Geosynchronous means the satellite’s orbital period matches the Earth’s rotation, so it completes one orbit in about 24 hours. The simplest way to achieve a 24-hour period with a stable, constant distance from Earth is a circular orbit. In a circular orbit, the radius stays fixed and the speed is constant, so the satellite can, in the right plane (often the equatorial plane), stay over roughly the same longitude relative to the surface. This is why a circular shape is the typical description for geosynchronous orbits.

Elliptical orbits can be tuned to have a 24-hour period as well, but the distance to Earth then varies during each orbit, causing the satellite’s ground track to move rather than stay fixed. Parabolic and hyperbolic shapes are unbound trajectories and don’t sustain a long-term orbit around Earth.