SpaceX is set to blast off a Falcon 9 rocket from California Saturday night on a secretive military mission.
The rocket is scheduled to launch at 6:50 p.m. From Vandenberg Space Force Base in Lompoc, according to the company’s announcement. If the launch is scrubbed, SpaceX has another shot Sunday at 2:38 p.m. The classified mission, dubbed USSF-366, could involve deploying a batch of military satellites into low-Earth orbit, according to several spaceflight outlets.
SpaceX announced late this week that it would serve as the launch provider for the US Space Force mission. The 230-foot Falcon 9 will haul the mysterious payload into space before its booster attempts to stick the landing on SpaceX’s drone ship, Of Course I Still Love You, in the Pacific Ocean. The controlled landing allows SpaceX to recover and reuse the booster for future missions.
Despite the cloak-and-dagger nature of the payload, SpaceX plans to livestream the launch beginning about 10 minutes before liftoff. Residents in Santa Barbara, San Luis Obispo and Ventura counties may hear one or more sonic booms during the launch, although what residents experience will depend on weather and other conditions.
Little is known about the details of USSF-366, including what exactly is tucked inside the two-stage rocket. Multiple spaceflight tracking sites have speculated the mission could deploy satellites based on SpaceX’s Starshield satellite bus, a military-focused variant of its Starlink platform. The speculation stems from locations of rocket stage drop zones being exact fits with previous Starlink Group 15 launches.
The Falcon 9 booster assigned to this mission, core B1088, is set to make its 18th flight. The booster previously launched NROL-126, Transporter-12, SPHEREx, NROL-57, and 13 Starlink missions. Following stage separation, the first stage will attempt its landing on the droneship stationed in the Pacific Ocean.
SpaceX stated people in nearby counties may hear one or more sonic booms during the launch. Whether the sounds reach the ground will depend on atmospheric conditions and local weather. The launches are typically visible across much of Southern California, as well as parts of Nevada and Arizona.
In the viral moment that sparked widespread attention to SpaceX’s classified military work, the company has increasingly become the go-to launch provider for national security payloads. The Hawthorne, California-based company won a National Security Space Launch Phase 2 contract in August 2020, cementing its role in launching sensitive government missions alongside United Launch Alliance. Previous top-secret launches for the National Reconnaissance Office and other agencies have followed similar patterns of minimal disclosure, with livestreams cutting off after payload fairing separation to protect classified hardware from public view.
The USSF-366 mission continues SpaceX’s rapid launch cadence from Vandenberg, with three Falcon 9 flights targeted from the California base in August alone. The company has already conducted dozens of launches from the site this year, mixing Starlink satellite deployments, commercial rideshare missions, and classified national security flights.
SpaceX posted on X that it was targeting Saturday, August 15 for the Falcon 9 launch of USSF-366 from Space Launch Complex 4E at Vandenberg Space Force Base. The company noted a backup opportunity would be available Sunday, August 16 if needed.
The live webcast will begin about 10 minutes before liftoff on the SpaceX website and on X, @SpaceX, according to the company’s standard practice for Vandenberg launches. Viewers typically see coverage through main engine cutoff, stage separation, and booster landing before the feed ends to protect the classified payload’s deployment sequence.
SpaceX’s next scheduled launch from Vandenberg after USSF-366 is a Starlink mission targeting August 18.