SpaceXFalcon 9 Block 5Space Launch Complex 4E, Vandenberg SFB, CA, USA
USSF-259
Launched
September 17, 2026 · 01:07 UTC
Image: SpaceX
Summary
Falcon 9 Block 5 launched USSF-259 from Vandenberg’s SLC-4E, successfully inserting its payload into target orbit. The classified mission for the U.S. Space Force may involve Starshield-based LEO satellites, with ascent drop zones matching prior SDA Transport Layer launches.
- Watch
- SpaceX USSF-259The Space Devs
- SpaceX Falcon 9 rocket launches from California on secretive U.S. Space Force missionSpaceflight Now
- USSF-259 MissionSpaceX
- Vehicle
- Falcon 9 Block 5 · SpaceX
- Booster
- B1097 · flight 13 · Autonomous Spaceport Drone Ship at Of Course I Still Love You · landed230/238 landed here · 28 days after its previous flight, Starlink Group 17-50 · 574 km downrange
- Mission
- Government/Top Secret · Polar Orbit (PO)for USSF
- Milestone
- 632nd Falcon 9 Block 5 flight · 106th this yearSpaceX's 729th launch110th this yearhumanity's 7,395th orbital launch attempt222nd orbital launch attempt this year
Flight preview
Orbit: representative
Target site default for this orbit type. Not a catalogued object; this panel switches to the tracked orbit once the object is catalogued. Ascent drawn from padside's representative profile. Booster return drawn from padside's representative arc.
Flight timeline
- T−38MGO for Prop Load
- T−35MProp Load
- T−35MStage 1 LOX Load
- T−16MStage 2 LOX Load
- T−7MEngine Chill
- T−1MTank Press
- T−1MStartup
- T−45SGO for Launch
- T−3SIgnition
- T−0Liftoff
- T+1M7SMax-Q
- T+2M26SMECO
- T+2M30SStage 2 Separation
- T+2M36SSES-1
- T+2M57SFairing Separation
- T+6M3SEntry Burn Startup
- T+6M24SEntry Burn Shutdown
- T+7M58SStage 1 Landing Burn
- T+8M20SStage 1 Landing
About this launch
USSF-259 launched on a SpaceX Falcon 9 Block 5 from Space Launch Complex 4E, Vandenberg SFB, CA, USA on September 17, 2026 at 01:07 UTC. The launch window ran from 01:00 to 05:00 UTC. It was SpaceX's 729th launch, 110th this year and humanity's 7,395th orbital launch attempt. It was the 632nd Falcon 9 Block 5 flight and the 106th this year. Booster B1097 flew for the 13th time and landed at Of Course I Still Love You. The payload was bound for Polar Orbit (PO).
USSF-259 is a classified mission for the United States Space Force. It is possibly a batch of classified LEO satellites based on SpaceX’s Starshield satellite bus, based on locations of ascent rocket stage drop zones being fits with previous SDA Transport Layer launches.
News
Live coverage: SpaceX to launch national security payload for the U.S. Space Force on Falcon 9 rocket from VandenbergThe rocket will carry an unspecified number of satellites to orbit. Liftoff from pad 4E at Vandenberg Space Force Base is scheduled for 7:18 p.m. PDT (10:18 p.m. EDT / 0218 UTC).
Launch Preview: Nine orbital launches scheduled from sites around the worldNine orbital launches are scheduled worldwide this week. Two Falcon 9s are expected to deliver…
Airspace and maritime notices
1 notice filed by the US Coast Guard
- Sector San Diego, Exclusive Economic Zone (EEZ)/Space Operations/Hazardous Warning Area/Commercial (Hazardous) · Expired
Matched by proximity to the pad · Source
Pad
Space Launch Complex 4E, Vandenberg SFB, CA, USA
297th launch from Space Launch Complex 4E, 59th this year · 913th from Vandenberg SFB, CA, USA
Local pad time at liftoff: Sep 16, 6:07 PM PDT, in daylight
303 launches from this pad · 919 from Vandenberg SFB, CA, USA
6 days 9 hours after the previous launch from this pad
Updates
Launch success.
Show 7 earlier updates
Liftoff.
Cosmic_Penguin · 9/17/2026 · source
Unofficial Re-stream by SPACE AFFAIRS has started
LL2 · 9/17/2026 · source
Now targeting Sep 17 at 01:07 UTC
Cosmic_Penguin · 9/16/2026 · source
Scrubbed for the day.
Cosmic_Penguin · 9/16/2026 · source
Now targeting Sep 16 at 02:18 UTC
Cosmic_Penguin · 9/15/2026 · source
Now targeting Sep 16 at 01:29 UTC
Cosmic_Penguin · 9/15/2026 · source
Added launch.
Cosmic_Penguin · 9/9/2026 · source
Questions
When did USSF-259 launch?
USSF-259 launched on September 17, 2026 at 01:07 UTC. The launch window ran from 01:00 to 05:00 UTC.
Where can I watch USSF-259?
Coverage: SpaceX USSF-259; SpaceX Falcon 9 rocket launches from California on secretive U.S. Space Force mission; USSF-259 Mission. Watch the replay
What rocket launched USSF-259?
Falcon 9 Block 5, flown by SpaceX. Falcon 9 Block 5 spec sheet
Where did USSF-259 launch from?
Space Launch Complex 4E, Vandenberg SFB, CA, USA. Liftoff was Sep 16, 6:07 PM PDT local time at the pad.
Did the booster land?
Booster B1097 flew for the 13th time and landed at Of Course I Still Love You.
What orbit was USSF-259 going to?
Polar Orbit (PO), a government/top secret mission.