NASA’s rehearsal for Artemis II marks one of the final steps before four astronauts get launched into deep space for the first time since the Apollo program ended.

NASA’s wet dress rehearsal—a crucial test of the agency’s Artemis II mission to the moon—hit a snag on Monday. 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.

With the wet dress rehearsal, essentially a critical fueling test of the Artemis 2 Space Launch System moon rocket, now back on Feb. 2, NASA said in a statement that it can no longer target Feb. 6 or Feb. 7, the first two days of its launch window. The Artemis 2 launch window originally ran from Feb. 6 to Feb. 10.

American space agency NASA said it fixed one of the RS-25 engines that was supposed to be part of the Artemis II mission, will now fly on Artemis IV.

Before NASA can decide a rocket launch date for Artemis 2, the giant SLS rocket has to ace a critical fueling test known as a wet dress rehearsal.

NASA's SLS rocket is scheduled to move to the launch pad this weekend for the Artemis II mission. A launch is targeted for no earlier than February 6, but the exact date depends on upcoming tests. Potential launch windows for the mission are available in ...