The Artemis II rocket is expected to roll out to the launch pad next week at the Kennedy Space Center.
If all goes according to plan, the mission could launch as early as April first, sending four astronauts on a journey around the moon. It would mark the first time humans travel to the lunar region in more than 50 years.
The mission was originally scheduled for earlier this year but was delayed after engineers discovered hydrogen fuel leaks and a helium-flow problem in the Space Launch System.
NASA returned the rocket to its assembly building for repairs before approving it for another launch attempt.
Officials say the launch window at the start of April is limited to six days before the next opportunity opens at the end of the month.
NASA’s acting science chief Lori Glaze says the flight is a test mission and carries risks, but engineers believe the rocket and crew are ready.
Meanwhile, the agency’s new administrator Jared Isaacman has announced changes to the Artemis program aimed at speeding up future moon missions.
Private companies SpaceX and Blue Origin are also developing lunar landers for astronauts, with the goal of supporting new moon landings later in the decade.
