Geostationary Orbit (GEO)

A high-altitude circular orbit, roughly 35,786 kilometers above the equator, where a satellite's orbital period exactly matches Earth's rotation — so it appears to hang motionless over one fixed point on the ground. Communications, weather, and space weather monitoring satellites rely on this orbit to keep continuous watch over the same region, but its high altitude also leaves spacecraft there directly exposed to solar energetic particles and geomagnetic disturbances with little atmospheric shielding.