NASA's massive SLS Moon Rocket rolls out to the launchpad

NASA kickstarts its Artemis Moon missions

If NASA's upcoming wet dress rehearsal goes to plan, SLS will be cleared to launch NASA's uncrewed Orion capsule around the Moon in the summer for Artemis I. The plan is then for Artemis II to send astronauts around the Moon, and for Artemis III to conduct the first astronaut Moon landing since 1972, the date of NASA's final Apollo moon landing.

At just under 100m in height, SLS is a massive launch vehicle, though it's a little smaller than SpaceX's full-stack Starship attached to a booster, which measures 120m. SLS was designed to be more powerful than the Apollo Saturn vehicles that took astronauts to the Moon in the 1960s and 70s.

SLS will have a payload capacity that will allow NASA to send more than 27 metric tons of cargo to the Moon as part of its goal of establishing a constant human presence on the Moon beyond Artemis III.

NASA has come under fire in recent months and years due to its SLS program going millions of dollars over budget. Some reports have even claimed NASA officials are "shitting the bed" over Starship's more advanced capabilities for a fraction of the cost when compared to its own SLS launch vehicle. It is telling that NASA decided to contract SpaceX's Starship vehicle for the crewed Artemis III Moon landing, rather than use its own rocket.

SLS's iconic rollout

Still, the first launchpad rollout of SLS is an iconic moment that signals the beginning of NASA's renewed ambitions to reach the Moon and then go further, eventually sending humans to Mars and beyond. It is the first time spectators will be able to see SLS with all of its components fully stacked together.

"The first rolling out of the VAB - that's really an iconic moment for this vehicle," said Tom Whitmeyer, Nasa's associate administrator for exploration systems development. "To be here for a new generation of a super-heavy-lift, exploration-class vehicle is a day to remember."

? @NASA_SLS and @NASA_Orion have arrived at Launch Complex 39B! The team will now begin final preparations ahead of the wet dress rehearsal test.

?: @nasahqphoto pic.twitter.com/Rym8s63jMg

— NASA's Kennedy Space Center (@NASAKennedy) March 18, 2022

The SLS rolled out of the Kennedy Space Center's Vehicle Assembly Building (VAB) at 18:00 local Florida time. As a rocket-carrying CT-2 goes at a top speed of just under 1mph, it took roughly 11 hours for the rocket to travel the 4 miles to the launchpad. By contrast, after liftoff, SLS will travel at a top speed of 6 miles per second, allowing the Orion capsule to reach a speed of 24,500 mph as it makes its way to the Moon, according to NASA. SLS's top speed would allow it to travel from New York to San Francisco in eight minutes.

During the rollout, the SLS itself was attached to a support gantry known as the Mobile Launcher, which is 120m tall. The wet dress rehearsal will likely take place on April 3, and liftoff will likely take place at some point in June or July.