Navigation Satellites fly at 23,000 km Altitude. Europe Wants to Build a Constellation That Flies Much, Much Lower

Distances to different orbits can be hard to understand. For example, the ISS sits around 400 kilometers from Earth, whereas some satellites, such as Starlink, orbit at about 550 km. Often that is intentional, as objects in those orbits will eventually degrade their orbit and burn up in Earth’s atmosphere. However, many systems orbit a …