NASA has set a date for the do-over of a key readiness test for its Artemis II mission to the moon. During this “wet dress rehearsal,” the agency will attempt to pump liquid fuel into the Space Launch System (SLS) rocket and simulate a countdown to liftoff on February 19 at 8:30 P.M. EST.
The test is critical for Artermis II to move forward for launch; the first attempt, performed on February 2, exposed problems with both the SLS and the Orion capsule, which is designed to house Artemis II’s four-person crew on a journey around the moon and back. Liquid hydrogen fuel leaked from the rocket, and one of the capsule’s valves malfunctioned. Notably, similar fuel leaks plagued the mission’s predecessor, Artemis I, delaying its launch for months.
In announcing the new wet dress rehearsal date, NASA said that engineers have replaced a filter in ground support equipment that they think reduced the flow of liquid hydrogen into the rocket and that this has potentially resolved the leaking issue.
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Unlike Artemis I, which was uncrewed, Artemis II will loft four people—NASA’s Reid Wiseman, Christina Koch, and Victor Glover and Canadian Space Agency astronaut Jeremy Hansen—into a record-breaking flyby around the moon.* For 10 days, the crew members will observe the moon’s little-studied farside and will perform other experiments onboard before they splash down in the Pacific Ocean off San Diego.
*Editor’s Note (2/17/26): This sentence was edited after posting to correct the description of Artemis II’s planned lunar flyby.
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