Artemis rocket heads back to its hangar for repairs as moonshot put on hold

NASA on Wednesday is set to roll its enormous Space Launch System rocket back to the hangar for repairs, a move that will delay the launch of four astronauts on a long-awaited flight around the moon by at least a month.

The 322-foot-tall rocket has been sitting out at the launch pad at Florida’s Kennedy Space Center since mid-January, but engineers recently found a blockage in the flow of helium to part of the booster’s upper stage that requires further investigation.

The rollback means NASA will no longer be able to attempt to launch the Artemis II mission in March. Agency officials said they could potentially try in April, but the timeline will depend on the outcome of the repairs.

“I understand people are disappointed by this development,” NASA Administrator Jared Isaacman wrote Saturday in a post on X. “That disappointment is felt most by the team at NASA, who have been working tirelessly to prepare for this great endeavor.”

Rolling the rocket back to its hangar is a major undertaking. The 4-mile journey, which is set to begin Wednesday morning at around 9 a.m. ET, is a famously slow one, and is expected to take up to 12 hours to complete. The 11-million-pound rocket, stacked with the Orion capsule on top, will be carried on a moving platform known as a crawler-transporter that will move at a snail’s pace of around 1 mile per hour.

Once the rocket reaches the hangar, called the Vehicle Assembly Building, NASA said teams will install platforms that will allow engineers to reach where the helium flow issues were detected.

The agency said batteries in the rocket’s upper stage and in a safety mechanism known as the flight termination system will also be replaced and tested while the booster is in the Vehicle Assembly Building.

The helium issue was uncovered in the overnight hours of Feb. 19, following what appeared to be a successful fueling test and launch-day walkthrough. The hourslong test, known as a wet dress rehearsal, was NASA’s second attempt to fully load the Space Launch System rocket with more than 700,000 gallons of cryogenic propellant and practice running through almost every step of a simulated launch countdown.

One day after the wet dress rehearsal, NASA officials announced that they were targeting March 6 to launch four crew members — NASA astronauts Reid Wiseman, Victor Glover and Christina Koch, and Canadian astronaut Jeremy Hansen — on a 10-day flight around the moon.

Now, the astronauts will have to wait at least a month for their moonshot. NASA’s launch window in April includes opportunities on April 1 and from April 3 through April 6, with an additional launch opportunity on April 30.

The Artemis II mission will be the first time that NASA’s Space Launch System rocket and Orion capsule carry people. A first wet dress rehearsal on Feb. 2 was stopped early after NASA detected leaking hydrogen at the tail end of the rocket. The leaks forced NASA to forgo all launch opportunities in February.

A previous uncrewed Artemis I flight around the moon in 2022 was delayed six months because of hydrogen leaks identified during its first wet dress rehearsal.

This article was originally published on NBCNews.com