NASA’s giant SLS rocket completes slow roll toward Artemis II moon voyage

FLORIDA - NASA astronaut Reid Wiseman said on the morning of Jan 17 that a few days earlier, he looked up and saw the crescent moon in the light of the sunrise. He thought about the far side of the Moon – the part that is always hidden from Earth.

“You just think about all the landmarks we’ve been studying on that far side and how amazing that will look,” he said at NASA’s Kennedy Space Center in Florida.

The former Navy captain is the commander of a mission called Artemis II, and the giant rocket that will send him on the trip that will provide him with those views was on the move – just not very fast or very far, yet.

On Jan 17, a mammoth crawler began transporting the Space Launch System (SLS) vehicle, the Orion capsule and the launch tower – 6.3 million kg altogether – from the Vehicle Assembly Building to the launchpad 6.7km away.

“This is the start of a very long journey,” said NASA administrator Jared Isaacman, as he and the four crew members of Artemis II talked with reporters while the rocket moved, almost imperceptibly, in the background.

The SLS crawler is one of two that NASA built in the 1960s to carry the Saturn V rockets during the Apollo programme and later modified for the space shuttles. Its peak speed is less than 1.6kmh, and it takes half a day for its trip from the Vehicle Assembly Building, which is essentially a large garage where the pieces of the 98m-tall rocket were put together.

It reached the launchpad at 6.42pm Eastern time. Now, final preparations will begin – hooking up connections for electrical power and propellants and performing checks of key systems.

That will lead to a dress rehearsal of the countdown in early February. The rehearsal will include filling the rocket’s propellant tanks with liquid hydrogen and liquid oxygen, performing the same tasks that will precede launch but stopping the countdown with 29 seconds left before the point when the engines would ignite. The propellant tanks will then be drained, and NASA engineers and officials will review the data.

The earliest possible launch date is Feb 6 with other opportunities until Feb 11.

“We have zero intention of communicating an actual launch date until we get through” the dress rehearsal, Mr Isaacman said.

If Artemis II does not launch by then, the next launch window would open in March.

If the dress rehearsal goes smoothly, NASA will aim to launch in February.

“I know the teams are prepared,” Mr Isaacman said. “I know this crew is prepared.”

Artemis II will carry Commander Wiseman along with Mr Victor Glover and Ms Christina Koch, also of NASA, and Mr Jeremy Hansen of the Canadian Space Agency. Mr Glover will be the first black man to fly by the Moon, Ms Koch the first woman and Mr Hansen the first non-American.

The rocket will loft the Orion capsule with the astronauts inside and send it on a 10.5-day trip swinging around the Moon without landing and then returning to Earth with a splashdown in the Pacific Ocean.

The SLS had been tested once before, during the Artemis I mission in 2022, but no astronauts were aboard then. The Orion was empty except for mannequins with sensors to measure vibrations, acceleration forces and radiation.

The key goal of Artemis II is to test a life-support system, which is not possible without humans aboard. The following mission, Artemis III, will be the big event when NASA astronauts step on the Moon again.

The destination will be somewhere near the lunar south pole, where frozen water can be found in shadowed craters, a potential resource for future missions.

NASA is aiming to launch Artemis III before the end of 2028, but many experts doubt that the lander needed to take the astronauts to the lunar surface – a version of the gigantic Starship vehicle under development by SpaceX, the rocket company led by Elon Musk – can be ready by then.

Both SpaceX and Blue Origin, owned by Amazon founder Jeff Bezos, have offered alternatives that could speed the development of a lander for Artemis III.

“I did meet with both Blue Origin and SpaceX on their acceleration plans,” Mr Isaacman said. “These are both very good plans. I would say they both reduce technical risk from where we were before.”

The Artemis II astronauts said they were ready for their trip around the Moon and had a chance to check out the Orion capsule during a countdown test while the rocket was still in the Vehicle Assembly Building.

Commander Wiseman recalled his glee that a button to dim the Orion display worked, unlike the one in the training simulator that never changed the screen’s brightness.

“I just want you all to remember we are four human beings getting in this magnificent spacecraft, and sometimes the simplest things put a huge smile on our face,” he said.

The astronauts also talked about conversations they have had with their families about the risks of something going fatally wrong during the journey.

“I went on a walk with my kids,” Commander Wiseman said. “I told them, ‘Here’s where the will is, here’s where the trust documents are, and if anything happens to me, here’s what’s going to happen to you.’ And that is a part of this life.”

Ms Koch also had some simpler matters to take care of with her husband.

“It’s not like the International Space Station, where we can just make a phone call,” she said. “So he’s not going to be able to call me and ask where something is in the house. He’s going to have to find it.” NYTIMES