Just one day after NASA said it was eyeing a potential March 6 launch date for the Artemis II lunar mission, the space agency said Saturday that complications with the rocket could delay all launch attempts in March from the Kennedy Space Center in Florida.
The Artemis II mission, which is set to carry four astronauts on a 10-day trip around the moon, would be the first time humans return to the vicinity of the moon since Apollo 17 in 1972.
In a blog post, NASA said it is "taking steps to potentially roll back the Artemis II rocket and Orion spacecraft to the Vehicle Assembly Building," after technicians observed an "interrupted flow of helium" to the rocket system. NASA says its teams are "actively reviewing data" and taking steps to "address the issue as soon as possible while engineers determine the best path forward."
NASA says a rollback from the pad to the nearby Vehicle Assembly Building would mean that the five potential launch dates in March would be off the table. NASA has six launch opportunities in April.
NASA says it's unclear why helium flow was interrupted. The space agency says it's reviewing data from the uncrewed Artemis I mission in 2022 in which teams had to troubleshoot helium-related pressurization of the upper stage before launch.
On Friday, following the completion of the second "wet dress rehearsal", NASA managers were optimistic. "This is really getting real," said Lori Glaze, acting associate administrator of NASA's exploration systems development mission directorate. "It's time to get serious and start getting excited."
A test of the rocket, earlier this month, revealed several issues. During the fueling, NASA encountered problems like a liquid hydrogen leak. Swapping out some seals and other work seems to have fixed those issues, according to officials who say that the latest countdown dress rehearsal went smoothly, despite glitches such as a loss of ground communications in the Launch Control Center that forced workers to temporarily use backups.
NPR's Nell Greenfieldboyce contributed reporting.
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