Artemis II re-entry LIVE: Astronauts prepare for splashdown return to Earth

The re-entry of the Orion spacecraft is by far the riskiest moment of the 10-day Artemis II mission to the moon.

The mission’s crew – Commander Reid Wiseman, pilot Victor Glover, and mission specialists Christina Koch and Jeremy Hansen – will hit the Earth’s atmosphere travelling at an astonishing 40,000km/h.

Watch NASA’s live coverage:

They’ll be enveloped in a fireball of plasma about half as hot as the surface of the sun.

We’re expecting the astronauts to splashdown in the Pacific Ocean off San Diego at 10.07am.

That will mark the end of the mission which has captured the world’s hearts and imagination, and saw humanity’s first fly-by visit to our lunar neighbour in 53 years.

NASA has said the US Navy and Department of War personnel are in place to help recover the Orion spacecraft and, more importantly, its four crew once they splash down in the Pacific Ocean about two hours.

Weather balloons are tracking the conditions for splashdown.

Helicopters and divers are ready to assist.

We are about 50 minutes from splashdown.

G’day! The Orion spacecraft is absolutely fanging it over Australia.

“We think we see a beautiful sunrise over the west coast of Australia,” Artemis II commander Reid Wiseman says.

“We copy,” replies mission control.

The spacecraft won’t be visible with the naked eye. But Australian CSIRO scientists helped track the Orion spacecraft throughout the mission from NASA’s Canberra Deep Space Communication Complex.

“In many ways this was a routine track for us,” CSIRO astronomer John Sarkissian told us.

A sonic boom could be heard in California as the Orion capsule scorches into the atmosphere, according to the United States Geological Survey.

It will be travelling at near-record speeds of 40,000km/h at its fastest – more 30 times the speed of sound.

The exact moment of splashdown has been updated to eight seconds after 10.07am (AEST).

The Orion spacecraft is about 20,000 kilometres from home.

Lead flight director of the Artemis II mission Jeff Radigan said yesterday the crew had to enter the atmosphere within an error margin “less than a degree of an angle”.

“Let’s not beat around the bush. We have to hit that angle correctly – otherwise we’re not going to have a successful re-entry,” he said.

(Are you nervous!? I’m nervous.)

Qualified astronaut and Australian of the Year Katherine Bennell-Pegg has followed the mission closely as director of space technology of the Australian Space Agency.

Who better to ask for the mission’s key highlights?

“I loved the human moments of the mission – the astronauts on the ISS and Artemis candidly chatting over comms, the crew proposing to name a bright spot on the moon after the commander’s late wife Carroll, the genuine ‘moon joy’ experienced by the astronauts, and a mission control filled with smart, powerful women,” Bennell-Pegg told us.

“My favourite moment was when, during the total solar eclipse, the crew witnessed live meteorite impacts on the lunar surface. The cameras on the spacecraft weren’t fast enough to capture the impact flashes – one of many examples of why humans are critical up there. Monitoring such impacts is so important, for understanding the risk to future missions and also the lunar environment.”

The Orion spacecraft’s return to Earth will begin the countdown to a boots-on-the-ground moon landing and, eventually, life on Mars.

But besides paving the way for NASA putting astronauts on the moon in 2028, what has the fly-by mission itself achieved?

Artemis II was the furthest and most epic journey ever undertaken by humans, and marked the first time we directly observed the far side of the moon.

As we’ve covered, all eyes are on the Orion spacecraft’s heat shield, which chaotically broke down and cracked last time it was tested in 2022.

The damage was caused by gas getting trapped in the shield when it re-entered the atmosphere, which then violently expanded and blew more than 100 chunks off the shield.

“They did a tremendous amount of research, a lot of groundbreaking research in some facilities that we had not used before, and they discovered the root cause,” Artemis II Commander Reid Wiseman said before launch.

“They did wind tunnel testing and laser testing and hyper-velocity testing, and they determined that if we come in with this lofted profile ... that this heat shield will be safe for us to go fly.

“So I think all that points in the direction of goodness … and I think if you, as a human being who was about to board this rocket, had sat in the meetings that we sat in and listened to the experts and gone through the data with them, you would have the same comfort.”

The astronauts hurtling back from the moon face the gravest danger of their journey in its final 15 minutes, when they’ll scorch through the atmosphere relying on a 7.5 centimetre-thick heat shield that failed during its last test.

The Orion spacecraft will also rocket back to Earth at 40,000km/h on an intense and untested trajectory.

When NASA last tested the heat shield during an uncrewed test-run in 2022, the heat shield cracked and lost about 100 chunks of material upon re-entry, instead of burning away evenly as designed.

The Artemis II crew began the last phase of their journey home by listening to Run to the Water by Live and Free by Zac Brown Band.

“We have to get back. There’s so much data that you’ve seen already, but all the good stuff is coming back with us. There are so many more pictures, so many more stories,” pilot Victor Glover said.

“Riding a fireball through the atmosphere is profound as well.”

The four returning astronauts must survive extraordinary speeds of 11 kilometres per second, withstand heat from a plasma fireball about half as hot as the sun, and brace for g-force of 3.9.

To achieve that, NASA has opted for a “lofted” entry sequence.

The spacecraft will dip into the atmosphere and skate along like a skimmed stone for a moment, rather than plunging straight down and exposing the crew to fatally high g-forces.

That allows the craft to decelerate more gradually before the final plunge to Earth.

It’s a modified manoeuvre compared to the full “skip re-entry” tested on Artemis I, which resulted in a chaotic and unexpected breakdown of its heat shield.

Even with the more gradual entry, the astronauts will be “getting the hell shaken out of them”, said University of Queensland expert in hypersonic aerothermodynamics Dr Chris James.