1 of 5 | People leave after the launch attempt of Artemis I, in the background on Launch Pad 39B, was scrubbed at Kennedy Space Center in Florida on Saturday. Photo by Pat Benic/UPI | License Photo
Sept. 3 (UPI) -- NASA postponed the Artemis I moon mission for at least 2 1/2 weeks Saturday after a fuel leak derailed the launch of the spacecraft for the second time.
The decision means the highly anticipated spacecraft will remain grounded at least through the remaining launch period which ends Tuesday. The next opportunities to launch fall between Sept. 19 and Oct. 4.
Saturday's launch was postponed as crews worked hours to fix a hydrogen fuel leak in the Space Launch System rocket. It was the second time a leak was blamed for a setback to the mission that will eventually return American astronauts to the moon for the first time in 50 years.
NASA will decide early next week whether to return the rocket to the massive Vehicle Assembly Building to diagnose and fix the hydrogen leak problem, which agency officials said at a media briefing Saturday certainly is not unique in rockets.
"We do not launch until we think it's right," NASA administrator Bill Nelson said during a the briefing that was broadcast live over the Internet. "These teams have labored over that and that is the conclusion they came to. I look at this as part of our space program, in which safety is at the top of the list."
Nelson, who said morale remained high among space workers, noted at the end of the briefing that "a scrub is much cheaper than a failure," and the such delays with new hardware are not to be unexpected.
The agency originally planned to launch the uncrewed Artemis I no earlier than 2:17 p.m. EDT Saturday from Launch Complex 39B at Kennedy Space Center in Florida.
Mission officials detected a liquid hydrogen leak around 7:15 a.m. in the quick disconnect cavity. This is what feeds hydrogen in the engine during the Space Launch System's core stage.
During a troubleshooting session Saturday morning, engineers were unable to plug the SLS leak. NASA commentator Derrol Nail said engineers warmed the area around which an 8-inch liquid hydrogen fuel line enters the propellant tank. They then pushed super-cold propellant through to seal the leak.
They also attempted to depressurize the line, Nail said, according to Space.com.
NASA paused its countdown clock for at least 30 minutes to address the leak. Initially it was unclear how much of a delay the issue would cause. It's possible engineers will be able to make up the time later.
The mission plans to fly an un-crewed Orion capsule to the moon, orbit and then return to Earth. The rocket would burn up in the atmosphere.
Once there, the spacecraft will enter Distant Retrograde Orbit, a long-distance orbit that will send Orion 40,000 miles past the moon. NASA said this plan will send Orion farther away from Earth than any previous spacecraft built to carry humans.
After being in that orbit for several days, Orion is to begin a closer orbit of the moon, before using the moon's gravity and its own engines to head back to Earth.
The Artemis I mission will provide data on how the rocket performs in deep space and will ultimately pave the way for future crewed flights around the moon and to the lunar surface.
Eventually, the Artemis program plans to return humans to the moon for the first time since 1972. NASA aims to send the first crewed Artemis mission to the moon in 2025.
That first crewed mission, Artemis III, is expected to put the first woman and person of color on the lunar surface.
The Space Launch System (SLS) rocket carrying an Orion spacecraft lifts off on the maiden flight of NASA's Artemis Program from Complex 39-B at the Kennedy Space Center on November 16, 2022. Photo by Joe Marino/UPI | License Photo