A SpaceX Falcon 9 lifted off at dawn on Saturday from Vandenberg Space Force Base in California on a mission to continue deployment of a secretive U.S. military satellite constellation.

Liftoff of the USSF-385 mission lifted off in dense fog at 7:00:54 a.m. PDT (10:00:54 a.m. EDT / 1400:54 UTC). The rocket took a southerly trajectory on departure from the pad at Space Launch Complex 4-East.

This classified mission for the U.S. Space Force is thought to be the third in a series of flights to deploy satellites based on SpaceX’s Starshield, a version of a Starlink satellite intended for government use. SpaceX said it was not showing views of the rocket’s payload or second stage at the request of its customer.

The first satellites in this particular constellation were launched from Vandenberg on USSF-366 on Aug. 15 and USSF-153 on Sept. 10. Although the Space Force revealed no details about the missions, it cataloged 23 satellites in orbit following each launch.

A similar classified mission, USSF-259, headed to a different orbit on Sept. 17 and appeared to carry 17 satellites.

The first stage booster, B1100, flew for a 10th time and landed on the drone ship ‘Of Course I Still Love You’, around eight and a half minutes after launch.

It was the sixth and final Falcon 9 launch of the month from Vandenberg, which has become the prime site for SpaceX as it shifts its focus at Cape Canaveral to Starship operations. Just one Falcon 9 flew from the company’s East Coast launch site in September.

• Falcon 9
• SpaceX
• USSF-385