Nasa has rolled its Artemis II rocket to the launch pad in Cape Canaveral ahead of a mission to send astronauts around the Moon for the first time in more than five decades.
The US space agency is hoping to use the SLS (Space Launch System) rocket and Orion spacecraft to send four astronauts around the Moon in their capsule before returning directly to Earth next month.
It is the second time this year that Nasa has rolled out its colossal moon rocket from its hangar to the launchpad, however teams identified an issue preventing helium from flowing to the rocket's upper stage, prompting a return to the Vehicle Assembly Building (VAB) where the issue was repaired.
While the rocket and spacecraft were in the VAB, engineers also refreshed and retested several systems on the rocket.
Artemis II will send Nasa astronauts Reid Wiseman, Victor Glover, and Christina Koch, along with CSA (Canadian Space Agency) astronaut Jeremy Hansen, on an approximately 10-day mission around the Moon and back, marking the first crewed flight of the Artemis programme.
The launch is a precursor to future missions that will enable humans to live on the Moon and mount crewed voyages to Mars.
The last time Nasa sent astronauts to the moon was during Apollo 17 in 1972. The new Artemis program aims for a two-person landing in 2028.
Late last month, Nasa's new administrator, Jared Isaacman, announced a major overhaul of the Artemis program.
Dissatisfied with the slow pace and lengthy gaps between lunar missions, he added an extra practice flight in orbit around Earth for next year.
That is now the new Artemis III, with the Moon landing by two astronauts shifted to Artemis IV. Mr Isaacman is targeting one and maybe even two lunar landings in 2028.
Nasa's Office of Inspector General previously warned in an audit that the space agency needs to come up with a rescue plan for its lunar crews.
Landing near the Moon's south pole will be riskier than it was for the Apollo astronauts closer to the equator given the rough polar terrain, according to the report.
Contracted by Nasa to provide the moon landers for astronauts, Elon Musk's SpaceX and Jeff Bezos' Blue Origin have accelerated work in order to meet the new 2028 target date.
The next test flight of SpaceX’s Starship rocket, which is contracted to deliver astronauts to lunar orbit, is expected to take place next month.
Additional reporting from agencies
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