LaunchLAUNCH SUCCESSFULLive

USSF-259

· Falcon 9 · Vandenberg, California

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01

Mission

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.

Falcon 9 launched USSF-259 from Space Launch Complex 4E (SLC-4E) at Vandenberg Space Force Base in California. This was the 13th flight for the first stage booster supporting this mission, B1097, which previously launched Starlink 17-50. After stage separation, the first stage landed on the Of Course I Still Love You droneship.

Launched
18:07 PDT at the pad
Rocket
Falcon 9 Block 5 · SpaceX
Destination
Polar Orbit
Launch site
Space Launch Complex 4E, Vandenberg, California 59th launch from this pad in 2026, 6 days after the previous
Latest update
Launch success.

240min

Launch window

13th

Flight of B1097

574km

Downrange landing, OCISLY

110th

SpaceX launch of 2026

02

Countdown

All times approximate · shown in your time zone, CEST · Timeline: The Space Devs

  1. T−00:38:00GO for Prop Load
  2. T−00:35:00Prop Load
  3. T−00:35:00Stage 1 LOX Load1st stage
  4. T−00:16:00Stage 2 LOX Load2nd stage
  5. T−00:07:00Engine Chill
  6. T−00:01:00Tank Press
  7. T−00:01:00Startup
  8. T−00:00:45GO for Launch
  9. T−00:00:03Ignition

03

Flight

All times approximate · shown in your time zone, CEST · Timeline: The Space Devs

  1. T+00:00:00Liftoff
  2. T+00:01:07Max-Q
  3. T+00:02:26MECO
  4. T+00:02:30Stage 2 Separation
  5. T+00:02:36SES-12nd stage
  6. T+00:02:57Fairing Separation2nd stage
  7. T+00:06:03Entry Burn Startup2nd stage
  8. T+00:06:24Entry Burn Shutdown2nd stage
  9. T+00:07:58Stage 1 Landing Burn1st stage
  10. T+00:08:20Stage 1 Landing1st stage

04

Falcon 9 Block 5

SpaceX · Reusable · 634 flights, 633 successful, first flown May 2018

  • BoosterB1097 · 13th flight · previously Starlink Group 17-50 · Droneship Of Course I Still Love You (OCISLY), landed
About Falcon 9 Block 5

Falcon 9 is a two-stage rocket designed and manufactured by SpaceX for the reliable and safe transport of satellites and the Dragon spacecraft into orbit. The Block 5 variant is the fifth major interval aimed at improving upon the ability for rapid reusability.

70m

Height

3.7m

Diameter

549t

Mass at liftoff

23t

Payload to low Earth orbit

7,607kN

Thrust at liftoff

05

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