Planets and Visitors · 9 of 12
Satellite Orbits
Why is the ISS round again in 90 minutes, while a TV dish never moves?
The ISS's orbit, drawn to scale round the globe, with polar, GPS and geostationary orbits: why each takes as long as it does, and where the geostationary belt sits in your sky.
You’ll be able to say why the ISS is round again in an hour and a half, and point to the geostationary belt.
Before this: Satellites and the ISS (6 min)
Where and which night
Working out when this is best placed from where you are…
Where
Kept for this guide only, until you change it here — your map settings, and every other guide, stay as they are.
Print, play outside or present
Scan with a phone's camera, or open
Sources
- Wikipedia, International Space Station — about 420 km up, at an inclination of 51.64°
- NASA, Spot the Station FAQ — the station circles the Earth about every 90 minutes and travels about 28,000 km/h (17,500 mph)
- USGS, Landsat 9 — a near-polar, Sun-synchronous orbit 705 km up, crossing the equator at 10:00 a.m. ± 15 minutes
- GPS.gov, Space Segment — about 20,200 km up, each satellite circling the Earth twice a day, in six orbital planes
- Wikipedia, Geostationary orbit — 35,786 km above the equator, one orbit per sidereal day; antennas can stay fixed on one point
- NGA, World Geodetic System 1984 (TR8350.2) — GM = 398,600.4418 km³/s² and the Earth's equatorial radius, 6,378.137 km
With a keyboard, focus the sky, aim it with the up and down arrow keys, and press Enter to drop the pin at the centre of the view; or press Show me.