How high is that orbit?
Orbit is not a place but a speed. These altitudes each buy a different trade between coverage, delay and lifetime.
Almost exactly International Space Station
400 km is higher than 2 of the 9 references on this page.
Reference figures are measurements and are rounded; the unit conversion behind them is exact.
| Reference | Size | Yours ÷ theirs | Note |
|---|---|---|---|
| airliner cruise | 11 km | 36.4× | |
| Kármán line | 100 km | 4× | |
| International Space Station | 408 km | 0.98× | |
| Hubble Space Telescope | 535 km | 0.748× | |
| Starlink | 550 km | 0.727× | |
| Earth-imaging satellites | 700 km | 0.571× | |
| GPS | 20,200 km | 1/50.5 | |
| geostationary orbit | 35,786 km | 1/89.5 | |
| the Moon | 384,400 km | 1/961 |
Worth knowing
- Geostationary orbit is at exactly 35 786 km, the one altitude where an orbit takes 24 hours and a satellite appears to hang still.
- The ISS loses about 2 km of altitude a month to atmospheric drag and needs regular reboosts to stay up.
Frequently asked
Why is geostationary orbit at that particular height?
Because orbital period depends only on altitude. At 35 786 km the period is exactly one sidereal day, so the satellite keeps pace with the rotating Earth.
Why does the ISS orbit so low?
Low orbit is far cheaper to reach, has a short radio delay and sits inside the Van Allen belts, which shields the crew. The cost is drag and frequent reboosts.