inner vanAZİZACAR outer vanallen belt graveyard orbit(geo+300 km) geostationaryearth orbit galileo beidoumeo satellites gps glonass iridium iss hubble 10000 km 20000 30000 40000 10000 mi 20000 radiusof orbit 10000 20000 30000 km 10000 20000 mi height abovesea level orbital period 5 hours 10 hours 15 hours 20 hours 25000 km/h 20000 km/h 15000 km/h 11000 km/h 15000 mph 10000 mph 7000 mph orbital speed