Updated 3 February 2026 at 11:24 IST
Artemis II Moon Mission Faces Critical Delay, NASA Flags Hydrogen Leak During 'Wet Dress Rehearsal'
NASA detected a hydrogen leak while conducting a critical fueling test of its astronaut-bound Moon rocket, prompting safety checks ahead of the Artemis mission. The issue highlights the technical and safety challenges NASA continues to face as it prepares to return humans to the Moon under the Artemis program.
NASA’s ambitious return to lunar exploration hit a familiar obstacle on Monday, February 2, 2026, as engineers detected a hydrogen leak during a high-stakes fueling test of the Space Launch System (SLS) rocket.
The "wet dress rehearsal" is the final major hurdle before the Artemis II mission can carry four astronauts around the Moon.
But the recurring technical issue has overshadowed the targeted launch date on February 8.
A Familiar Foe Returns
The problem arose at the Kennedy Space Centre as ground teams began the complex process of pumping over 700,000 gallons of super-cold liquid hydrogen and oxygen into the 322-foot-tall rocket.
Barely two hours into the operation, sensors flagged excessive hydrogen concentrations at the base of the vehicle, the critical connection point between the mobile launcher and the rocket.
This is not the first time hydrogen has obstructed the Artemis program.
The SLS in 2022 was tormented by similar leaks, which delayed the uncrewed Artemis I mission for months.
While NASA engineers applied "lessons learned" from those previous failures, the molecular nature of liquid hydrogen, the smallest element, continues to challenge the seals and fittings of the massive launch vehicle.
Managing the Countdown
Despite the leak exceeding safety limits twice on Monday, launch controllers successfully employed workarounds developed during the 2022 campaign.
By adjusting flow rates and transitioning the tanks to "refill mode," teams stabilised leak levels and proceeded with the simulated countdown.
The crew for Artemis II, Commander Reid Wiseman, Victor Glover, Christina Koch, and Canada’s Jeremy Hansen, monitored the rehearsal from Houston.
They have been in quarantine for over a week, awaiting the results that will determine if they can become the first humans to visit the lunar vicinity in over 50 years.
Narrow Launch Window
NASA is now under immense pressure to analyse the data from Monday’s test. The current launch window is exceptionally tight.
Target Launch: February 8, 2026
Deadline: February 11, 2026
Contingency: Postponement to March 2026
If engineers determine the leak requires physical repairs rather than just operational workarounds, the historic 10-day journey around the far side of the Moon will likely be pushed to late March.
Published By : Namya Kapur
Published On: 3 February 2026 at 11:20 IST