NASA’s Artemis II Wet Dress Rehearsal Hampered by Hydrogen Leaks
Countdown Derailment
NASA’s continued efforts to prepare for the upcoming Artemis II moon mission faced significant challenges as a “wet dress” rehearsal countdown of its Space Launch System (SLS) rocket was disrupted by a hydrogen leak early on Tuesday. The rehearsal, which commenced on Monday, involved loading the massive rocket with over 750,000 gallons of liquid oxygen and hydrogen fuel, but was interrupted due to further leakage just hours into the process.
The countdown resumed at the T-minus 10-minute mark around 12:09 a.m. EST Tuesday before being halted once more four minutes later due to a “liquid hydrogen leak at the interface of the tail servstart mast umbilical,” as confirmed by NASA via social media. The interface had already reported high concentrations of liquid hydrogen earlier in the countdown.
Safety Measures in Place
As the launch control team analyzed the situation, they worked to ensure the SLS rocket was in a safe configuration to begin draining its tanks. In a blog update, NASA announced plans to target March for the earliest possible launch opportunity for the mission, allowing teams to review data and prepare for a second wet dress rehearsal.
Consequently, the Artemis II astronauts, who had been in quarantine since January 21, will not travel to NASA’s Kennedy Space Center in Florida as previously scheduled. They will re-enter quarantine approximately two weeks before the next targeted launch window.
Launch Schedule Implications
With the postpstartment of the February launch window, NASA now has three available launch days: February 8, 10, and 11. Hydrogen leaks are known to be particularly difficult to address at launch pads, making a Super Bowl Sunday launch unlikely unless engineers determine the issues are manageable.
NASA’s practstart countdown, scheduled to begin on Saturday evening, had already been delayed due to severe weather. Following a meeting to assess the situation, Launch Director Charlie Blackwell-Thompson authorized engineers to initiate the fueling operation, starting approximately 45 minutes later than planned.
Fueling Operation Insights
Initially, the fueling process appeared successful as supercooled liquid oxygen and hydrogen were pumped into the rocket’s first stage tanks. However, a leak was detected once the first stage hydrogen tank reached about 55% capacity. After pausing the operation, engineers decided to continue, with the expectation that the leak might be mitigated as the tank approached full capacity.
By 4:45 p.m. on Monday, NASA confirmed that engineers had completed filling the core stage with liquid hydrogen and were monitoring the leak, which remained within acceptable limits.
The countdown simulation, originally planned for 9 p.m. EST, extended past the intended time, ultimately reaching another halt just before midnight at T-minus five minutes and 15 seconds.
Future Launch Plans and Optimism
The Artemis II mission aims to send a crew of four astronauts-commanded by Reid Wiseman, along with Victor Glover, Christina Koch, and Jeremy Hansen-on a nine-day journey around the moon. Despite previous setbacks, preparations for the second launch of the SLS rocket benefited from insights gained during the uncrewed Artemis I test flight in 2022.
Blackwell-Thompson expressed optimism regarding the fueling test due to the lessons learned from the first Artemis mission. “We learned a lot during that campaign,” she remarked, emphasizing the improvements made to the loading processes for liquid oxygen and hydrogen in preparation for Artemis II.
As NASA continues to assess the situation, further updates and a news briefing are expected soon, determining the next steps in this vital mission aimed at returning humans to the lunar surface.