Low Earth orbit

The region of orbits from roughly 160 to 2,000 km altitude, home to the International Space Station and most active satellites.

• At the station's roughly 400 km, orbital speed is about 7.7 km/s and one lap of Earth takes about 90 minutes.
• Satellites stay up by falling around Earth: they move sideways so fast that the surface curves away beneath them.
• Being close gives sharper imaging and signal delays of roughly 20–40 ms, versus about 600 ms round trip via geostationary orbit.
• Each satellite covers a small area and passes quickly, so global service needs thousands; Starlink runs over 8,000, raising collision concerns.