SpaceX launching 2nd classified mission for US Space Force in less than a week tonight: Watch it live

SpaceX is set to launch its second secret mission for the U.S. Space Force tonight, September 15, from California's Vandenberg Space Force Base. A Falcon 9 rocket will take off during a four-hour window that begins at 9 p.m. EDT (6 p.m. local California time; 0100 GMT on September 16). The launch will be accessible live via SpaceX's webcast, which begins about 10 minutes prior to liftoff.

However, little information is available about tonight's mission, codenamed USSF-259. The launch webcast is expected to conclude shortly after the first stage of the Falcon 9 returns to Earth via a drone-ship landing, approximately 8.5 minutes post-launch. This landing marks the 13th for this particular booster, designated 1097.

Booster 1097 recently achieved a significant milestone in April when it performed SpaceX's 600th touchdown of an orbital-class rocket during a mission that deployed 25 Starlink internet satellites into low Earth orbit. This upcoming launch will be SpaceX's 110th of 2026, with the majority of these flights conducted by the workhorse Falcon 9, totaling 105 so far this year.

The powerful Falcon Heavy has also been launched twice this year, while SpaceX's next-generation megarocket, Starship, has flown twice this year, both times as suborbital test flights. The next Starship launch, anticipated within the next two weeks, will mark the vehicle's first orbital flight.