Nasa said that its early March launch day for its highly anticipated lunar mission would almost definitely be pushed back, after the agency spotted problems with the system's helium flow in safety checks.
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But overnight on Friday, engineers observed an interruption in the flow of helium required for launch operations.

"This will almost assuredly impact the March launch window," NASA said in a statement on Saturday, adding that it would almost definitely delay its highly anticipated lunar mission.

https://www.bbc.co.uk/news/articles/c626v265zqlo

Nasa to launch historic Artemis II moon mission on 6 March after delays

Nasa said on Friday it was planning to launch its delayed Artemis II moon mission on 6 March after successfully completing a fueling test that had caused it to stand down earlier this month.

Jared Isaacman, the space agency’s newly confirmed administrator, cited “major progress” since the original so-called wet dress rehearsal in which engineers discovered liquid hydrogen leaking from the space launch system (SLS) rocket on its Florida launchpad at Cape Canaveral.

The mission’s four astronauts, three Americans and one Canadian, were entering a second period of quarantine on Friday in anticipation of the new target launch date, which Nasa announced “with caveats” because it said there was still much preparatory work to do after Thursday’s fueling test.
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Nasa has several dates available in early March to launch Artemis, which will conduct a 10-day trip around the moon, but not land. The flight will take humans further into space then ever before and, according to Nasa, the mission will fly about 4,700 miles (7,600km) beyond the far side of the moon, surpassing the distance record set by Apollo 13 in 1970. The mission will test systems for future deep-space exploration.

https://www.theguardian.com/science/2026/feb/20/nasa-artemis-ii-moon-mission-launch