A dress rehearsal countdown for NASA’s Artemis II moon rocket, intended to clear the way for a possible February launch, ran into a variety of problems and ultimately was called off early Tuesday because of an out-of-limits hydrogen leak. Shortly after, NASA announced the long awaited flight to send four astronauts on a trip around the moon, was being delayed to March at the earliest.”With the conclusion of the wet dress rehearsal today, we are moving off the February launch window and targeting March for the earliest possible launch of Artemis II,” NASA Administrator Jared Isaacman said in a post on X.”We fully anticipated encountering challenges,” he said. “That is precisely why we conduct a wet dress rehearsal. These tests are designed to surface issues before flight and set up launch day with the highest probability of success.”AdvertisementAdvertisementArtemis II commander Reid Wiseman, Victor Glover, Christina Koch and Canadian astronaut Jeremy Hansen, in pre-flight medical quarantine at the Johnson Space Center in Houston, had hope to fly to Florida Tuesday to begin final preparations for launch. Instead, they will remain in Houston and rejoin family, friends and co-workers.The practice countdown began Saturday evening — two days late because of frigid weather along Florida’s Space Coast — and after a meeting Monday morning to assess the weather and the team’s readiness to proceed, Launch Director Charlie Blackwell-Thompson cleared engineers to begin the remotely-controlled fueling operation.NASA’s Space Launch System rocket stands atop pad 39B at the Kennedy Space Center on night of Feb. 2, 2026. / Credit: NASA(NASA)The test got underway about 45 minutes later than planned, but it initially appeared to be proceeding smoothly as supercold liquid oxygen and hydrogen fuel were pumped into the Space Launch System rocket’s first stage tanks. Shortly after, hydrogen began flowing into the rocket’s upper stage as planned.But after the first stage hydrogen tank was about 55% full, a leak was detected at an umbilical plate where a fuel line from the launch pad is connected to the base of the SLS rocket’s first stage. After a brief pause, engineers resumed fuel flow but again cut it off with the tank about 77% full.AdvertisementAdvertisementAfter more discussion, engineers were able to press ahead by stoppin …
