NASA once again halted its Artemis I Space Launch System (SLS) wet dress rehearsal Monday evening—the second time this week.
Previously, the rocket encountered a temperature limit issue that paused the countdown for several hours on Sunday. The rocket’s propellant, liquid oxygen, is an extremely cold liquid that must be maintained at minus 297 degrees Fahrenheit.
After resolving the temperature issue, the team encountered another issue Monday—this time involving a panel that controls the core stage vent valve. The team managed to fill the tank up to 50 percent capacity, but the valve issue prevented them from relieving pressure from the core stage during fueling.
“I’m confident we’re going to get through the wet dress in fairly short order,” Artemis mission manager Mike Sarafin told reporters during a teleconference Sunday. “We’ve just got to work through these problems.”
Since the teams were nearing the end of their shifts, the launch director called off the test for the remainder of the day.
NASA is expected to hold a teleconference at 4 p.m. Tuesday to provide additional updates to Artemis I’s final major test, which originally started Friday and was expected to last two days.
Artemis I, the first of several trips back to the moon, will be uncrewed—circling the moon and splashing back down in the Pacific Ocean. Crewed missions will begin in phase two of the program, and will eventually land the first woman and person of color on the lunar surface as soon as 2026.
Following the completion of the rehearsal, the SLS will be drained of all fuel and rolled back into the Vehicle Assembly Building (VAB) for additional preparations for launch.