Fuel Leak Discovery Forces NASA to Postpone Artemis Moon Mission Test Run

In a recent update, NASA has revealed a shift in its timeline for the Artemis II mission, now eyeing a March launch due to fuel leaks discovered during testing procedures this week. This mission marks a significant milestone, aiming to transport astronauts around the moon for the first time in over half a century. Scheduled to launch from the iconic Launch Complex 39B at NASA’s Kennedy Space Center in Florida, the mission will utilize the Space Launch System—NASA’s most formidable rocket to date.

The space agency detailed its progress, stating, “NASA concluded a wet dress rehearsal for the agency’s Artemis II test flight early Tuesday morning, successfully loading cryogenic propellant into the SLS (Space Launch System) tanks, sending a team out to the launch pad to close out [the] Orion [spacecraft], and safely draining the rocket. The wet dress rehearsal was a prelaunch test to fuel the rocket, designed to identify any issues and resolve them before attempting a launch.” This meticulous procedure is crucial for troubleshooting and ensuring a smooth launch when the time comes.

Despite encountering several obstacles during the two-day testing window, NASA engineers managed to accomplish many of their intended goals. The agency noted, “Engineers pushed through several challenges during the two-day test and met many of the planned objectives. To allow teams to review data and conduct a second wet dress rehearsal, NASA now will target March as the earliest possible launch opportunity for the flight test.”

In a striking visual, a full moon was captured illuminating NASA’s Space Launch System and Orion spacecraft atop the mobile launcher, set against the early morning backdrop of February 1, 2026, at Kennedy Space Center. This image, courtesy of Sam Lott/NASA, underscores the celestial ambitions of the Artemis II mission, even as earthly challenges necessitate a cautious approach.

A full moon is seen shining over NASA’s SLS (Space Launch System) and Orion spacecraft, atop the mobile launcher in the early hours of Sunday, Feb. 1, 2026, at NASA’s Kennedy Space Center in Florida.  (Sam Lott/NASA via AP)

NASA said earlier this morning that, “The Artemis II wet dress rehearsal countdown was terminated at the T-5:15 minute mark due to a liquid hydrogen leak at the interface of the tail service mast umbilical, which had experienced high concentrations of liquid hydrogen earlier in the countdown, as well.” 

“Moving off a February launch window also means the Artemis II astronauts will be released from quarantine, which they entered in Houston on Jan. 21,” according to NASA. “As a result, they will not travel to NASA’s Kennedy Space Center in Florida Tuesday as tentatively planned. Crew will enter quarantine again about two weeks out from the next targeted launch opportunity.” 

The agency gave no indication of an official launch target in March, saying teams need to first “fully review data from the test, mitigate each issue, and return to testing.” Before Tuesday’s postponement, the earliest NASA could have launched commander Reid Wiseman and his crew to the moon was no sooner than Sunday. 

NASA’s Artemis II sits in the Vehicle Assembly Building at NASA’s Kennedy Space Center on Jan. 16, 2026 in Cape Canaveral, Fla.  (Joe Raedle/Getty Images)

Launch controllers Monday began loading the 322-foot rocket with super-cold hydrogen and oxygen at midday. More than 700,000 gallons had to flow into the tanks and remain on board for several hours, mimicking the final stages of an actual countdown. 

But excessive hydrogen quickly built up near the bottom of the rocket. Hydrogen loading was halted at least twice as the launch team scrambled to work around the problem using techniques developed during the previous Space Launch System countdown in 2022. That first test flight was plagued by hydrogen leaks before finally soaring without a crew. 

Artemis II follows the uncrewed Artemis I mission and will serve as a critical test of NASA’s deep-space systems before astronauts attempt a lunar landing on a future flight.

The NASA Artemis II SLS (Space Launch System) rocket with the Orion spacecraft is seen at Launch Complex 39B at the Kennedy Space Center, on Sunday, Feb. 1, 2026, in Cape Canaveral, Fla. (AP/John Raoux)

NASA says the mission is a key step toward long-term lunar exploration and eventual crewed missions to Mars.