GPS III

GPS III, the newest generation of GPS satellites, carries all the signals of the Block IIF satellites before it and adds a fourth civil signal, L1C, along with enhanced reliability, accuracy and integrity. It has no Selective Availability, and each satellite is designed to last 15 years.

The first GPS III satellite was originally expected to be available for launch in April 2014. Development problems, mainly with its navigation payload, pushed that back by years, and the first one launched in 2018. The tenth and last, Space Vehicle 10, launched on a SpaceX Falcon 9 from Cape Canaveral on April 21, 2026, after which the Space Force counted 32 satellites in the active constellation.

The satellites are flown from Schriever Space Force Base, Colorado, by the Space Force’s 2nd Navigation Warfare Squadron and the Air Force Reserve’s 19th Space Operations Squadron. The next generation, GPS III Follow-On, is also built by Lockheed Martin.

Read more about GPS III

• How GPS turns atomic time into position, and who keeps it runningA receiver finds itself by timing signals from four satellites. The Space Force runs the system, finished GPS III in April 2026, and canceled the ground system that was meant to replace the old one.
• Why the station, Landsat, GPS, GOES and Webb fly where they doHeight sets a satellite’s speed; tilt and shape set what it sees. Five neighborhoods, from the station about 400 km up to Webb 1.5 million km away, and the work each one makes possible.