The **wet dress rehearsal** officially commenced on Tuesday evening and extended into Wednesday, with the team powering up both the rocket and spacecraft components while charging flight batteries. The crucial part of this test began on Thursday morning when mission managers approved the fueling of the **Space Launch System (SLS) rocket**.
At around **10:30 a.m. ET**, liquid hydrogen and liquid oxygen were initiated into the rocket’s core stage. The booster housed over **700,000 gallons of cryogenic propellant**, and mission managers executed a countdown leading up to a simulated launch time of **8:42 p.m. ET**.
The **refueling test** appeared to proceed smoothly, with NASA performing two walkthroughs during the last 10 minutes of the countdown. A pause occurred at approximately **T minus 1 minute and 30 seconds**, followed by a reset of the countdown clock to **T minus 10 minutes** near **T minus 33 seconds** for the final moments before liftoff.
These pauses were meticulously designed to demonstrate that the rocket’s systems were functioning as anticipated during critical countdown phases, when automated systems assume control of the booster. Additionally, these moments allowed mission managers to rehearse various scenarios, including resolving issues that necessitate investigation or aborting a launch due to technical difficulties or adverse weather conditions.
Source: www.nbcnews.com
