SpaceX confirmed today, April 20, 2026, that it has completed final pre-flight preparations for the GPS III Space Vehicle 08 (GPS III-8) mission. The launch is scheduled for tomorrow, April 21, from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida. This mission marks the deployment of the tenth and final satellite in the current Global Positioning System III (GPS III) block, representing the conclusion of a multi-year effort by the U.S. Space Force to modernize the nation’s positioning, navigation, and timing infrastructure.
The GPS III-8 satellite, formally designated SV10 and named "Hedy Lamarr" in honor of the actress and inventor of frequency-hopping technology, was manufactured by Lockheed Martin. According to technical specifications from the U.S. Space Force, the GPS III series provides up to three times greater accuracy and up to eight times improved anti-jamming capabilities compared to the older GPS IIF satellites. The "Hedy Lamarr" satellite also features the L1C civil signal, designed for interoperability with international systems like Europe’s Galileo, and the encrypted M-code signal for military users.
The mission was originally contracted to United Launch Alliance (ULA) but was reassigned to SpaceX by the Space Systems Command (SSC) to ensure the rapid delivery of advanced capabilities. This decision followed a change in the National Security Space Launch (NSSL) manifest to maintain the constellation’s resilience while ULA continues investigations into its Vulcan rocket program. Colonel Ryan Hiserote, the NSSL system program director, stated today that the strategic emphasis remains on the agility and responsiveness of the launch program to deliver capabilities to orbit as soon as prudent.
For tomorrow’s mission, SpaceX will utilize a Falcon 9 first-stage booster, tail number B1095, which is making its seventh flight. Following stage separation, the booster is scheduled to land on the droneship "Just Read the Instructions" in the Atlantic Ocean. The use of flight-proven hardware has become a standard component of the Space Force’s launch strategy to reduce costs and increase the frequency of national security missions.
The GPS III program has involved significant capital investment, with the first ten satellites carrying a total estimated program cost of approximately $5.8 billion. Lockheed Martin was awarded the primary contract for the design and production of these units. Following the successful deployment of GPS III-8, the Space Force will transition to the GPS III Follow-On (GPS IIIF) program. Lockheed Martin is currently under contract to build 20 GPS IIIF satellites, which are expected to begin launching in 2027 and will feature even more advanced regional military protection capabilities.
Weather conditions for the 2:53 a.m. ET launch window are currently reported as 90 percent favorable. Once operational, the GPS III-8 satellite will bring the total active GPS constellation to 32 satellites, providing enhanced redundancy and signal strength for billions of users worldwide.