The US Space Force has attached formal names to the two most ambitious moving-target satellite programs of its history, confirming Northrop Grumman as prime for a Resilient Radar System-Ground (RRS-G) constellation that will track terrestrial targets and lining up the first prototype launches of a SpaceX-built airborne moving-target indication (AMTI) fleet before the end of September.
RRS-G: a name and a prime for GMTI
Speaking at the AFA Air, Space and Cyber conference outside Washington, Lt. Gen. Gregory Gagnon, deputy chief of space operations for intelligence, said the Space-Based Ground Moving Target Indicator (SB-GMTI) program has been redesignated the Resilient Radar System-Ground and that Northrop Grumman is now formally on contract as prime. The program is being co-developed with the National Reconnaissance Office and will target tanks, surface ships and mobile troop formations from low Earth orbit. RRS-G launches are expected within the next two years, and the Space Force in August stood up the 77th Surveillance Squadron to operate the constellation from the ground segment out.
SB-AMTI: SpaceX launches this month
The complementary Space-Based Airborne Moving Target Indicator (SB-AMTI) program moves faster. Secretary of the Air Force Troy Meink confirmed on the same stage that "we are launching our AMTI — or our air-moving target indication constellation — this month," with SpaceX under a $4.16 billion prime contract for the operational build. Rocket Lab picked up a $397 million subcontract earlier this quarter for its Flatellite variant. Three additional firms are working on novel sensing payloads inside the SB-AMTI architecture. Full global coverage is not expected until 2028, but the first prototypes will feed data back to refine the Golden Dome-adjacent architecture that Congress has been funding at a rising clip.
Why moving-target radar from orbit matters
Both constellations replace legacy JSTARS-style airborne radars with resilient orbital networks. "Our need as a joint force to track mobile targets is essential to war-winning capabilities," Gagnon told the conference. The pairing of ground-focused RRS-G with airborne-focused SB-AMTI gives US commanders on-orbit sensor fusion against every kind of mobile threat and closes gaps that adversaries have exploited by dispersing air defence, radar and missile launchers.
What comes next
Rocket Lab's Flatellite bus for SB-AMTI has already flown demonstrator hardware and is expected to be part of the September launch cadence. Northrop's RRS-G designs sit on top of technology accumulated from earlier NRO reconnaissance programs and from the company's joint work on Air Force autonomy testing. Analysts expect the Space Force to disclose further RRS-G launch milestones once the initial constellation is on contract for production quantities.
Reporting based on coverage from Breaking Defense, DefenseScoop and Air & Space Forces Magazine.