A geostationary satellite appears fixed in the sky because its orbital period matches Earth's rotation period exactly. This is physics, not magic — and it requires a very precise altitude.
A geostationary satellite appears fixed in the sky because its orbital period matches Earth's rotation period exactly. This is physics, not magic — and it requires a very precise altitude.
At GEO altitude, a satellite moves at 3.07 km/s — faster than any aircraft. It just moves at exactly the right speed to stay over the same longitude. GEO slots are so valuable that the ITU allocates them like property.
Some orbits appear semi-stationary for specific regions without being true geostationary.
Understanding this explains why GEO satellites need station-keeping, why their dishes can be fixed, and why they dominate broadcast and regional communications.