Four astronauts blasted off from Florida on Wednesday on Nasa's Artemis II mission, a high-stakes 10-day trip around the moon that marks the first crewed flight around Earth's natural satellite in more than 50 years.

Nasa's Space Launch System (SLS) rocket, topped with its Orion crew capsule, roared to life just before sunset at the agency's Kennedy Space Centre to lift its first crew of three US astronauts and a Canadian astronaut off Earth, a thunderous ascent leaving behind a towering column of thick white vapour.

The Artemis II crew of Nasa astronauts Reid Wiseman, Victor Glover and Christina Koch and Canadian Space Agency astronaut Jeremy Hansen are poised for a nearly 10-day expedition around the moon and back, taking them deeper into space than humans have ever gone.

Five minutes into the flight, Commander Wiseman saw the target: “We have a beautiful moonrise we're headed right at it,” he said from the capsule

After nearly three years of training, they are the first group to fly in Nasa's Artemis program, a multibillion-dollar series of missions created in 2017 to build up a long-term US presence on the moon over the next decade and beyond.

The launch was a major milestone more than a decade in the making for the US space agency's SLS rocket, handing its core contractors Boeing and Northrop Grumman long-sought validation that the 30-story-tall system can safely loft humans into space, as Nasa increasingly relies on newer, cheaper rockets from Elon Musk's SpaceX and others.

The crew's gumdrop-shaped Orion capsule, built for Nasa by Lockheed Martin, will separate from the SLS upper stage 3-1/2 hours into flight in Earth's orbit. The crew will then take manual control of Orion to test its steering and manoeuvrability around the detached upper stage, attempting the first of dozens of test objectives planned throughout the mission.

Tensions were high earlier in the day as hydrogen fuel started flowing into the rocket. Dangerous hydrogen leaks erupted during a countdown test earlier this year, forcing a lengthy flight delay.

To Nasa’s relief, no significant hydrogen leaks occurred.

Nasa also had to deal with some issues beforehand but was able to resolve them and allow the launch to proceed without delay, one of them related to commands not getting through to the rocket's flight-termination system, which is needed to send a self-destruct signal in case the rocket veers off course and threatens populated areas.

That issue was quickly resolved, according to Nasa. It also had to troubleshoot one of the batteries in the capsule's launch-abort system. Launch controllers scrambled to understand why the battery's temperature was out of limit. Ultimately, it didn't prevent the launch from taking place.

The Artemis II mission is a key early step in the flagship US moon program, which is targeting its first crewed landing on the lunar surface in 2028 in the Artemis IV mission.

Nasa is pressed to achieve that lunar landing - its first since the final Apollo mission in 1972 - as China expands its own lunar programme with a planned astronaut landing as soon as 2030. (Agencies)



Edited by Cecil Wong