If the mission proceeds as planned, the astronauts will set a record by venturing further from Earth than any human before.
It is also the inaugural crewed flight of Nasa’s new lunar rocket, dubbed SLS.
The mammoth orange-and-white rocket is designed to allow the United States to repeatedly return to the Moon, with the goal of establishing a permanent base that will offer a platform for further exploration.
“It’s a stepping stone to Mars, where we might have the most likelihood of finding evidence of past life, but it’s also a Rosetta Stone for how other solar systems form,” Koch told reporters on the weekend.
Repeated setbacks
Under bright Florida sunshine, four giant tanks on the rocket started filling with liquid hydrogen and oxygen at 8.35am.
A full load of fuel will boost the rocket’s weight by 1000 tonnes, for a total of more than 2600 tonnes.
The mission was originally due to take off as early as February.
But repeated setbacks stalled the mission and even necessitated rolling the rocket back to its hangar for analysis and repairs.
As of Tuesday afternoon, Nasa officials voiced confidence that engineering operations and final preparations were proceeding smoothly.
If Wednesday’s launch is cancelled or delayed, there are more liftoff opportunities through to Monday, although weather later in the week was looking slightly less favourable.
About 400,000 people were expected to watch the launch, local media reported.
“We’re looking forward to it, we’ve never seen anything like this,” 76-year-old retiree Melinda Schuerfranz of Ohio told AFP.
But Schuerfranz remembers the Apollo era, and thinks some of the magic might be lost in today’s fragmented media environment.
“I think it was way more exciting then,” she said. “Everybody tuned into it.”
‘Astronauts for Halloween’
Artemis is facing pressure from President Donald Trump, who has pushed the pace of the programme that’s aiming to see boots hit the lunar surface before his second term ends in early 2029.
Artemis 2’s objectives include verifying that both the rocket and the spacecraft are in working order to pave the way for a Moon landing in 2028.
That deadline has raised eyebrows among experts, in part because Washington is relying on the private sector’s technological headway.
The astronauts will require a second vehicle to descend to the moon’s surface, a lunar lander that remains under development by rival space companies owned by billionaires Elon Musk and Jeff Bezos.
This contemporary era of American lunar investment has frequently been portrayed as an effort in competition with China, which is aiming to land humans on the moon by 2030.
For Nasa head Jared Isaacman, it’s a multi-pronged pursuit related to scientific discovery, national security and economic opportunity – as well as some less tangible goals.
“I guarantee after these astronauts fly around the moon, you’re going to have more kids dressing up as astronauts for Halloween,” Isaacman said during a recent interview.
“And that’s going to inspire the next generation to take us further.”
– Agence France-Presse