Week in Space Data, every Friday.
This launch has flown
Liftoff
Counts are flown launches (successes, partial failures and failures) in the SpaceNexus launch record for the calendar year, up to and including this one. The outcome is Launch Library 2’s own label. Booster serials and reuse counts are not in our records; the provider publishes them.
No webcast was linked to Atlas V 551 · Amazon Leo (KA-02) in the launch feed. The provider's own channel is the place to look for a replay.
Liftoff Jun 23, 2025, 10:54 UTC. Live chat ran from two hours before liftoff to two hours after.
Every entry is a change we recorded, not a forecast. Our sync checks Launch Library 2 every 15 minutes, so a time is when we saw the change and can trail the real moment. The liftoff time is the one the launch record states.
Liftoff
from the launch record
Outcome in the launch record: Success
time not in the recordfrom the launch record
Atlas V (United Launch Alliance)
Atlas V flies a first stage powered by one Russian-built RD-180 engine and a Centaur upper stage with RL10 hydrogen engines, with up to five solid boosters depending on the version. ULA is flying out its remaining Atlas V rockets.
Source: ULA: Atlas V, checked 2026-09-27The provider's page for this flight
The broad sequence of an orbital launch. Details and times differ by rocket and mission; this is a guide, not live tracking.
In the last part of the count the rocket is fuelled, systems switch to internal power and the launch team is polled for a go.
The first-stage engines ignite and the rocket leaves the pad.
The moment of maximum aerodynamic pressure on the rocket during ascent.
The spent first stage separates and the upper stage takes over. Some rockets also drop side boosters earlier in the climb.
The upper stage burns to reach the planned orbit, sometimes in more than one burn with a coast in between.
The payload separates from the upper stage. On a crewed flight the capsule separates and flies on under its own power.
Checking for a discussion…
Part of a tracked program. See it on the Amazon Leo (formerly Project Kuiper) tracker, with the program's contracts, satellites and launch slips.