Updated May 11, 5:07 p.m. EDT (2107 UTC): Added some additional context from the NRO.
The National Reconnaissance Office is set to fly its 13th mission supporting an intelligence-gathering constellation it calls the “proliferated architecture.”
As with the first dozen missions, this batch of satellites (of an undisclosed quantity) will fly to orbit on a SpaceX Falcon 9 rocket. The mission, dubbed NROL-172, will launch from Space Launch Complex 4 East at Vandenberg Space Force Base on Monday evening.
Liftoff is scheduled for 7:13:50 p.m. PDT (10:13:50 p.m. EDT / 0213:50 UTC), nearly four hours after the opening of the window.
Spaceflight Now will have live coverage beginning about 30 minutes prior to liftoff.
SpaceX will launch the mission using the Falcon 9 first stage booster with the tail number B1103. This will be its second flight following the launch of the Starlink 17-35 mission on April 7.
At 8.5 minutes after liftoff, B1103 will target a landing on the drone ship, ‘Of Course I Still Love You’, positioned in the Pacific Ocean. If successful, this will be the 196th landing on this vessel and the 610th booster landing to date for SpaceX.
Given the nature of reconnaissance operations, the NRO doesn’t offer much detail on these satellites or specifics on their capabilities. It did state in its prelaunch press kit that having hundreds of satellites as part of this constellation will “provide greater revisit rates and increased coverage, and eliminate single points of failure.”
For this mission, the NRO did add some additional information by noting that its Geospatial Intelligence Systems Acquisitions Directorate (GEOINT) is contributing to the satellite constellation.
“GEOINT’s contribution to the NRO’s proliferated architecture includes electo-optical, radar, and relay satellites,” the NRO said. “Additionally, these relay satellites enable inter-satellite optical communications and serve as a key component of the NRO’s resilient communications architecture as well as the Department of War’s (DoW) upcoming space-data network.”
The NROL-172 mission is the second flight booked on a Falcon 9 rocket as part of the National Security Space Launch (NSSL) Phase 3 Lane 1 contract, managed by the United States Space Force’s Space Systems Command (SSC). The first of those was the NROL-145 mission, which launchd on April 20, 2025.
The two missions were assigned to SpaceX as part of the NSSL Task Order (NTO)-2 on Oct. 18, 2024.
“The Lane 1 path is ideal for shorter, more responsive mission timelines in addition to being the ideal entry avenue for prospective NSSL providers,” said USSF Col. Jim Horne, Launch Execution Senior Materiel Leader,” in a press release at the time.
Since the launch of NROL-145, there were two other missions supporting the proliferated architecture constellation: NROL-48 on Sept. 22, 2025, and NROL-105 on Jan. 16, 2026. Those two missions secured for launch onboard SpaceX Falcon 9 rockets through a procurement structure outside of the SSC’s NSSL program
In a statement to Spaceflight Now on Monday, a NRO spokesperson said it sometimes used procurement structures outside of the NSSL contract, as a bridge between the conclusion of NSSL Phase 2 and of Phase 3 Lane 1. Like with all the missions leading up to NROL-145, a NRO spokesperson said both the NROL-48 and NROL-105 missions were procured using “the same structure as with earlier proliferated launches.”
“During a satellite system acquisition lifecycle, cost, schedule, and performance analyses are completed to determine the best way to develop, acquire, launch, and operate systems to meet Intelligence Community and warfighter requirements,” the spokesperson said. “During those analyses, NRO makes decisions to meet those requirements most efficiently and effectively. For NRO’s proliferated architecture, NRO recognized a bridge was needed between Phase 2 to Phase 3 Lane 1. This resulted in some missions being procured outside of NSSL. Going forward, future proliferated architecture missions will be launched with a mix of NSSL Phase 3 Lane 1 and missions procured through other acquisition vehicles.”
“The NRO has been a staunch supporter of NSSL since its inception and is committed to using National Security Space Launch (NSSL) Phase 3 for major system acquisitions,” the NRO spokesperson said. “The NRO is partnered with USSF Space Systems Command’s Assured Access to Space Team in the acquisition of Phase 3 and influenced the development of Phase 3, Lane 1 – as a means of procuring flexible launch solutions with tailorable mission assurance.”
“When considering our launch cadence and need for tailorable mission assurance, the NRO recognized that we needed a bridge between Phase 2 to Phase 3 – Lane 1. This resulted in some missions being procured outside of NSSL. NSSL has, and will continue to be, the NRO’s principal mechanism to procure launch services.”
