Overview
- A Falcon 9 is set to lift off from Vandenberg Space Force Base in a four‑hour evening window that opens at 6 p.m. PT on Tuesday, Sept. 15, and SpaceX will stream a webcast starting about ten minutes before liftoff.
- The payload for USSF‑259 is classified, a federal agency confirmed, and public tracking shows it is expected to be placed into low Earth orbit at roughly an 80° inclination.
- SpaceX assigned first‑stage booster B1097 to the flight, which will be the booster’s 13th mission and is planned to return to the droneship Of Course I Still Love You about 8.5 minutes after launch.
- USSF‑259 is one of several recent national‑security flights procured by Space Systems Command under the NSSL Phase 3 program and follows similar classified launches earlier in September with a commercial Starlink flight also scheduled from Vandenberg on Sept. 19.
- Because the mission is classified, public details and the webcast are likely to end soon after first‑stage recovery and local authorities warn the southerly trajectory could limit ground visibility and produce sonic booms depending on weather.