NASA has delayed the first US manned mission to the moon in more than half a century until September 2026 "to work through the challenges" on developing and integrating the spacecraft systems in the Artemis program, US space agency administrator Bill Nelson told reporters on Tuesday.

"To give [the] Artemis teams more time to work through the challenges with first time developments, we are going to give more time on Artemis II and Artemis III," Nelson told a teleconference.

"We are adjusting our schedule to target Artemis II for September of 2025 and September of 2026 for Artemis III which will send humans for the first time to the lunar south pole."

NASA officials explained at the news conference that the delay to both the planned Artemis II mission to fly around the moon and back, and then the follow up planned Artemis III manned landing at the lunar South Pole were being delayed to give time to deal with unanticipated problems.

These involved the development of new spacesuits, unanticipated detachment of material from the reentry heat shield on the unmanned Artemis I mission last year and failures with the Orion spacecraft life support system and new abort ejection mechanism for its astronauts.