NROL-172

Mission

NROL-172 on Falcon 9 Block 5. Tue 12 May 2026, 02:13:50 UTC. Reported outcome: Success. Launch site: Space Launch Complex 4E. Source: Launch Library 2.

Thirteenth batch of satellites for a reconnaissance satellite constellation built by SpaceX and Northrop Grumman for the National Reconnaissance Office to provide imaging and other reconnaissance capabilities.

Mission type

Government/Top Secret

Orbit

Low Earth Orbit

Rocket file imagery

Launch timeline

Times are relative to liftoff.

1. T-38 minTue 12 May, 03:35 CEST

   GO for Prop Load

   Launch director verifies go for propellant load

2. T-35 minTue 12 May, 03:38 CEST

   Prop Load

   Start of propelland loading

3. T-35 minTue 12 May, 03:38 CEST

   Stage 1 LOX Load

   Start of liquid oxygen loading in the first stage

4. T-16 minTue 12 May, 03:57 CEST

   Stage 2 LOX Load

   Start of liquid oxygen loading in the second stage

5. T-7 minTue 12 May, 04:06 CEST

   Engine Chill

   Start of engine chilling

6. T-1 minTue 12 May, 04:12 CEST

   Tank Press

   Fuel tanks are pressurized to flight levels

7. T-1 minTue 12 May, 04:12 CEST

   Startup

   The onboard computer takes control over the countdown and runs last checks

8. T-45 sTue 12 May, 04:13 CEST

   GO for Launch

   Launch director verifies go for launch

9. T-3 sTue 12 May, 04:13 CEST

   Ignition

   Start of the engine ignition sequence

10. T-0Tue 12 May, 04:13 CEST

    Liftoff

    First upwards movement of the rocket

11. T+1 min 6 sTue 12 May, 04:14 CEST

    Max-Q

    Maximum dynamic pressure

12. T+2 min 25 sTue 12 May, 04:16 CEST

    MECO

    Cut-off of the main engine

13. T+2 min 29 sTue 12 May, 04:16 CEST

    Stage 2 Separation

    Separation of the second stage from the first

14. T+2 min 36 sTue 12 May, 04:16 CEST

    SES-1

    First start of the second engine

15. T+2 min 53 sTue 12 May, 04:16 CEST

    Fairing Separation

    Separation of the payload fairing

16. T+6 min 15 sTue 12 May, 04:20 CEST

    Entry Burn Startup

    Start of the atmospheric entry burn

17. T+6 min 38 sTue 12 May, 04:20 CEST

    Entry Burn Shutdown

    End of the atmospheric entry burn

18. T+8 min 6 sTue 12 May, 04:21 CEST

    Stage 1 Landing Burn

    Start of the first stage landing burn

19. T+8 min 30 sTue 12 May, 04:22 CEST

    Stage 1 Landing

    Landing of the first stage

Slip history

Changes recorded by Space Right Now

No changes since we started tracking on Sat 10 Oct 2026, 11:18 UTC.

Launch pad

Space Launch Complex 4E

Vandenberg SFB, CA, USA (US)

Coordinates: 34.632, -120.611