Artemis I Update: Rocket’s Upper Stage Powered Up, Countdown on Track

The Space Launch System rocket’s interim cryogenic propulsion stage (ICPS) has been powered up, the NASA test director has given the “go” for booster power up, and all non-essential personnel have left the launch pad area in preparation for propellant loading operations.

At 10:53 p.m. EDT, or L-9 hours, 40 minutes, the launch team is expected to reach a planned two hour, 30-minute built-in hold. During this time, the mission management team will review the status of operations, receive a weather briefing, and make a “go” or “no-go” decision to proceed with tanking operations.

Tanking milestones include filling the rocket’s core stage with several hundred thousand gallons of liquid oxygen and liquid hydrogen. This will occur over a series of different propellant loading milestones to fill and replenish the tanks.

At midnight, NASA TV coverage begins with commentary of tanking operations to load propellant into the SLS rocket. Full coverage begins at 6:30 a.m.