NASA delays Artemis II to March after hydrogen leaks bedevil countdown test

NASA has concluded a Wet Dress Rehearsal (WDR) for Artemis II, but recurring liquid hydrogen leaks forced the test to be halted short of completion, prompting the agency to delay the mission's launch to at least March 2026.

The extra time will be used to work through the issues that arose during the test before a second WDR.

The biggest problem was a liquid hydrogen leak. A leak in the interface that routes cryogenic propellant into the rocket's core stage delayed engineers as the team opted to stop the flow of liquid hydrogen in the hope that warming the interface would allow the seals to reseat.

Eventually, the tanks in both the core stage and the interim cryogenic propulsion stage were filled, and the countdown could go ahead, but it was halted again at the five-minute mark ...