NASA has successfully transitioned all cryogenic tanks on the Space Launch System (SLS) rocket to replenish mode during the Artemis II wet dress rehearsal. This critical phase involves both liquid hydrogen and liquid oxygen tanks for the core stage and the interim cryogenic propulsion stage.
Key Operations in Artemis II Wet Dress Rehearsal
Engineers are actively monitoring the concentration levels of liquid hydrogen in the tail service mast umbilical. A leak had previously been detected, but current levels are stable. Cryogenic propellants warm and evaporate over time, even in insulated tanks, which is why replenishment is vital.
- Replenish mode continuously adds small amounts of liquid hydrogen and liquid oxygen.
- This maintains proper levels and pressure within the tanks.
- It ensures the rocket remains fully fueled as the countdown progresses.
Countdown Progression and Final Checks
Following the replenishment of all stages, teams will conduct final system checks. This includes verifying the performance of valves and sensors before moving on to the terminal countdown sequence. This sequence simulates launch operations and includes final readiness verifications.
The countdown clock has entered a 40-minute hold, a new element compared to the Artemis I mission. With all stages now in replenish mode, the Artemis II wet dress rehearsal is in its final fueling configuration, bringing operations closer to terminal count.
Launch Complex Preparations
NASA’s closeout crew is preparing to head to Launch Complex 39B. Their primary goal is to ensure safety and readiness during this critical phase of fueling operations. A 24/7 live stream of the rocket at the pad continues to provide updates, along with a dedicated feed for wet dress activities.
