Geostationary orbit (GEO)
Also known as: GEO, geostationary orbit, geosynchronous equatorial orbit, Clarke orbit
A geostationary orbit (GEO) is a circular orbit about 35,786 kilometres above the equator where a satellite takes exactly one day to circle the Earth, so it appears fixed in the sky.
That's why satellite TV dishes can point at one spot and never move. While GEO satellites cover huge areas with just a few spacecraft, their distance creates a noticeable delay, which is why internet services have shifted toward low Earth orbit.
Geostationary orbit (GEO), explained at three levels
At home
Picture two runners on a circular track, one on an inner lane and one far out, paced so they always stay side by side. A geostationary satellite does that with Earth: about 35,786 kilometres above the equator, it takes exactly one day to circle, matching the planet's spin. From the ground it seems frozen in one spot, so a TV dish can be aimed once and left alone.
At work
Geostationary orbit is a single ring above the equator where satellites appear fixed in the sky. Because each satellite sits so high, it sees a huge area, and three can cover most of the populated world. Businesses rely on GEO for TV distribution, weather imaging, ship and aircraft connectivity, and backup links, because fixed antennas are simple and one satellite can serve a whole country.
At home
The height is not a choice. Orbital speed depends on altitude, and only at about 35,786 kilometres does one lap take exactly one sidereal day, about 23 hours and 56 minutes. The satellite must also sit over the equator, or it would drift north and south in the sky. The cost of that height is delay: a signal takes about a quarter of a second to go up and down, so an internet round trip takes around 600 milliseconds, enough to make video calls stutter.
At work
Because there is only one ring, GEO positions are scarce. Operators apply through national regulators, and the International Telecommunication Union coordinates orbital slots and frequencies so neighbours don't interfere. Each satellite carries transponders that receive a signal, shift its frequency, amplify it, and send it back down. Older satellites used wide beams covering a continent. High-throughput satellites, such as Viasat's, use many narrow spot beams that reuse frequencies to multiply capacity. Small thruster burns keep each satellite inside its assigned box.
At home
A GEO satellite sits over the equator, so the farther north you live, the lower it appears on your horizon. In Iqaluit it is barely above the hills, and past roughly 81 degrees north it disappears entirely. Low-angle signals also pass through more atmosphere and are easily blocked by terrain. While GEO served Canada well for TV and phone links since Anik A1, in my view its geometry is a big reason the Arctic waited so long for decent internet.
At work
A GEO satellite typically lasts 15 years or more, limited mainly by the fuel it uses to hold position. At end of life, operators boost it about 300 kilometres higher into a graveyard orbit to free the slot, following Inter-Agency Space Debris Coordination Committee guidelines. Failure modes include rain fade at higher frequencies such as Ka-band, sun outages near the equinoxes, and latency that breaks interactive apps. Many operators, including Telesat and SES, now sell multi-orbit services combining GEO with LEO.
Real-world examples
At home
Marcus watches satellite TV at his cottage in Muskoka. The dish points at one fixed spot in the southern sky because the satellite sits over the equator, moving with Earth's rotation.
At work
Nadia manages communications for a Canadian shipping company. Her fleet uses GEO satellites for reliable coverage across oceans, adding LEO service for crew internet where latency matters more.
How it compares
| feature | Geostationary orbit (GEO) | Low Earth orbit (LEO) satellite constellation |
|---|---|---|
| Position in sky | Fixed | Moving constantly |
| Dish type | Fixed pointing dish | Electronically steered antenna |
| Latency | High | Low |
| Arctic coverage | Poor | Good with polar orbits |
GEO stays put but is far away. LEO is close but always moving.
For analysts
For applications sensitive to delay, such as voice calls or remote control, GEO links can be frustrating. I'd match the orbit to the use case rather than assuming all satellite internet performs the same.
History & origin
Science fiction writer Arthur C. Clarke described using geostationary satellites for global communications in a 1945 article. Syncom 3, launched in 1964, became the first geostationary satellite and broadcast parts of the Tokyo Olympics to the United States. Canada's Anik A1, launched in 1972, was the world's first domestic geostationary communications satellite, linking northern communities. GEO became the standard for TV broadcasting, weather satellites, and satellite internet. Satellite internet from GEO, such as Viasat and HughesNet, served rural areas but with high latency. In my view, Anik A1 is an underappreciated Canadian achievement that shows how satellites have always mattered more in a country this big.