Astronauts are again bound for the moon. Their mission could be a game-changer for mankind

Space exploration will make an enormous leap this week when four astronauts slingshot around the moon and become the most extreme travellers in all of human history, soaring to the farthest point from Earth ever reached by mankind.

But this new era of lunar travel isn’t about reaching space. It’s about staying there.

Experts say NASA’s Artemis II mission signals the start of the transition from short-term space missions to long-term occupation – and one day, colonisation – of the moon and distant planets.

“This mission is monumental. It’s about more than going back to the moon; it’s about proving we can operate sustainably beyond Earth,” said Swinburne University of Technology space expert Dr Matt Shaw. “This is where it all starts.”

Scientists have trained their focus on extracting resources from the lunar soil, including metals, building materials, oxygen and possibly water, to support human outposts.

One of those is Belinda Rich, a space researcher also from Swinburne, who said Artemis II marked a milestone in humanity’s move towards a self-sustaining ecosystem in space.

“We’re going to the moon, to stay, and it’s those extra words that change everything,” she said of the five-stage Artemis missions.

Hydrogen fuel leaks and a clogged pressurisation line delayed Artemis II’s initial launch by months.

Then, on Tuesday morning, NASA triggered the official countdown to blast-off.

What to expect from Artemis II

Artemis II is a 10-day lunar flyby mission where four astronauts will loop around the moon without landing, and return to Earth.

NASA’s 100-metre tall Space Launch System rocket is expected to blast off from NASA’s Kennedy Space Centre in Florida about 6.24pm on Wednesday, local time, or 9.24am on Thursday AEDT.

The rocket will launch the Orion spacecraft into Earth’s high orbit, carrying four astronauts in a module with room comparable to two minivans. The crew includes NASA’s Reid Wiseman, Victor Glover and Christina Koch and Canadian astronaut Jeremy Hansen.

The spacecraft will loop Earth twice as the crew practise piloting manoeuvres, test its operations, and ensure life support systems can generate breathable air.

The Orion craft will also establish communications with NASA’s Deep Space Network, a trio of powerful radio stations including the Tidbinbilla station just outside Canberra, which provides critical coverage for NASA when spacecraft are beyond Earth’s orbit.

Orion will then perform a “translunar injection burn” which will jet the astronauts on a four-day, figure-eight trajectory looping around the far side of the moon.

That will take them as far as humans have ever gone, about 7400 kilometres from the far side of the moon and 400,000 kilometres from Earth.

“From the crew’s location, the moon will look about the size of a basketball held at arm’s length,” NASA said. The astronauts will lay eyes on parts of the moon never directly observed by humans.

The spacecraft will hijack the moon’s own gravity to slingshot back towards Earth – a manoeuvre that should work even in the event of a propulsion failure.

The craft will splash down into the Pacific Ocean and the astronauts will hitch a ride home with the US Navy.

The mission follows on from Artemis I, when the Orion spacecraft was sent on an uncrewed lunar orbit.

Why is NASA going back to the moon?

The Artemis II mission is a crucial part of NASA’s efforts to land astronauts on the moon by 2028. Every data point concerning crew health, systems performance and safety will be funnelled into its mission to establish a long-term lunar presence.

No one has walked on the moon since Gene Cernan, commander of NASA Apollo 17 mission, in 1972.

There was little incentive to fund enormously expensive future moon landings in the decades after the US beat the Soviet Union to the lunar surface in 1969.

After the space race was won, “the geopolitical reason for continuing those missions really wasn’t there”, director of the Space Policy Institute at George Washington University, Scott Pace, told The Conversation.

But as the technological ability to inhabit deep space – or another planet – comes closer to reality, and geopolitical competition intensifies, the incentive has returned.

Both China and Russia are gunning to set up a nuclear-powered village on the moon within 10 years. And, as Pace said, the “rules are made by people who show up”. (Experts have said China is outpacing its rivals.)

The Artemis missions are the US’s attempt to get there first and win the Space Race 2.0, with the ultimate goal of transforming the moon into a launchpad for getting to Mars.

Just last week, though, NASA abandoned its plans to build a space station in the moon’s orbit, dubbed the Lunar Gateway. It said it would build a $US20 billion base on the moon instead.

How is Australia involved?

The Canberra Deep Space Communication Complex, which is managed by the CSIRO for NASA, is one of three primary crucial stations that will allow two-way chatter between the Artemis II astronauts and mission control once the spacecraft leaves low Earth orbit. The other two stations are in Spain and California.

The famed 64-metre wide Murriyang telescope in Parkes will also be put to work by US space company Intuitive Machines, which NASA invited to help track the Orion craft.

The Quantum Optical Ground Station at Mount Stromlo Observatory will also transmit and receive laser signals from the spacecraft, said Australian project lead for Artemis II Professor Francis Bennet, in a bid to improve our ability to communicate throughout the solar system.

The Australian National University project will help to trial the new laser communication method on board.

The laser system could make the transmission of data 100 times faster than radio waves.

With current technology, talking to astronauts on Mars would theoretically have a 20-minute delay, which would be impractical at best and catastrophic in an emergency.

The CSIRO has rolled out its new Mobile Operations Centre truck – like a mission control room melded with a semi-trailer – for ANU to use during the mission.

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