NASA's Artemis II launch rehearsal hits a snag

"Engineers had been fueling the mission's Space Launch System (SLS) rocket up with liquid hydrogen and liquid oxygen propellant and planned to initiate a countdown sequence to simulate the launch. But hours into the process, NASA engineers stopped the flow of liquid hydrogen into the core stage of the SLS, which houses the rocket's main engines, to investigate and troubleshoot a potential leak."

"Liquid oxygen (the other main component of the rocket's fuel) is still flowing into the core stage. As part of the troubleshooting effort, NASA has paused liquid hydrogen loading into the upper stage, which was designed to loft the Orion crew capsule toward its orbital journey around the moon. Fuel leaks also plagued the predecessor to Artemis II in testing and held up the launch of that mission, Artemis I, for weeks."

Engineers paused liquid hydrogen flow into the Space Launch System (SLS) core stage hours into Artemis II wet dress rehearsal to investigate a potential leak. Liquid oxygen continues flowing into the core stage. Hydrogen loading into the upper stage was also paused as part of troubleshooting efforts; the upper stage was designed to loft the Orion crew capsule toward lunar orbit. Fuel leaks delayed testing for Artemis I as well. Artemis II will carry four astronauts on a roughly 10-day loop around the moon and back, taking humans farther into space than before. If the wet dress rehearsal succeeds, the mission could launch no earlier than February 8.

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