Artemis I: Nasa cancels moon mission launch over engine problem

They were unable to find a fix in time to meet a two-hour launch window that opened at 8.33am (1.33pm BST) on Monday, and they are now troubleshooting the issue to assess readiness for the next available opportunity, on Friday 2 September.

If Artemis 1 ultimately succeeds, astronauts will be onboard an interim test flight along the same route 40,000 miles beyond the moon and back, a trek scheduled for 2024. The first moon landing since Apollo 17 in December 1972 would follow a year or so later, with Nasa declaring it will carry the first woman to walk on the lunar surface.

But the Nasa administrator, Bill Nelson, a former space shuttle astronaut, said there was greater purpose in placing new human footprints in lunar soil now from those of the 12 men of the Apollo programme who did so over six missions in a past generation.

The ESM will push Orion farther from Earth than any human-rated space vehicle has ever flown before, providing electricity, water, oxygen and nitrogen and keeping the capsule on course and at the correct temperature before separating and burning up harmlessly in the atmosphere on its return to Earth.