LOS ANGELES, Feb. 3 (Xinhua) -- The National Aeronautics and Space Administration (NASA) said it concluded a wet dress rehearsal for the Artemis II crewed lunar mission on Tuesday, with the countdown halted due to a liquid hydrogen leak.
About five minutes before the simulated engine ignition on early Tuesday, the ground launch sequencer automatically stopped the countdown due to a spike in the leak rate, according to the agency.
NASA Administrator Jared Isaacman said the agency targets March for the launch of Artemis II, shifting away from the February launch window.
The wet dress rehearsal, a full prelaunch test, was designed to fuel the rocket and identify any issues before an actual launch. NASA began the countdown at 8:13 p.m. Eastern Time on Saturday (0100 GMT Sunday).
The rehearsal encountered several setbacks. Among the issues, low temperatures at Kennedy Space Center in Florida delayed the start of fueling as some interfaces required time to reach acceptable operating temperatures.
During tanking operations, engineers troubleshot a liquid hydrogen leak at a core-stage interface by stopping the flow of liquid hydrogen, allowing the interface to warm for seals to reseat, and adjusting propellant flow, according to NASA.
In addition to the hydrogen leak at the final prelaunch operations, another delay was caused by a recently replaced valve associated with the Orion crew module hatch pressurization requiring retorquing.
The Artemis II mission will send four astronauts on an approximately 10-day journey around the Moon and back. The crew consists of NASA astronauts Reid Wiseman, Victor Glover and Christina Koch, and Canadian Space Agency astronaut Jeremy Hansen. ■
