13.2.4—A satellite in a geostationary orbit remains at the same point above the

A geostationary satellite stays above one longitude because it orbits eastward in Earth’s equatorial plane with the same angular speed and period as Earth’s rotation.

All three conditions matter: circular orbit, equatorial plane and synchronous period. Its apparent fixed position is relative to the rotating Earth.

Communications dishes can point at a geostationary satellite without tracking it across the sky.

Any satellite with a 24-hour period is not automatically geostationary if its orbit is tilted or elliptical.