In pictures: NASA’s powerful moonshot rocket debuts at Kennedy Space Center

The maiden mission, Artemis I, is T-minus two months away.
Orange NASA SLS rocket at launchpad at Kennedy Space Center in Florida with a brown banner that says "we are going"
More than 10 years in the making, NASA's Space Launch System rocket is finally feeling out a launch pad for the first time to prepare for the Artemis I uncrewed mission. NASA/Kim Shiflett

NASA’s most powerful rocket, called the Space Launch System (SLS), rolled to the launch pad at Kennedy Space Center on March 18 and is wrapping up its first “wet dress rehearsal” in the next day or two. The moon-bound SLS will shuttle the uncrewed Orion spacecraft during the Artemis I mission (currently scheduled for May 2022) and a crewed capsule with the Artemis II mission (slated for 2024, but likely launching much later). At 322 feet tall and 3.5 million pounds, it’s one of the largest rockets ever built—and will produce 15 percent more thrust than the Saturn V vehicle behind the final Apollo lunar missions.

The wet dress rehearsal involves fueling drills and a mock clocking system, according to a NASA update on the mission page. “Now at the pad for the first time, we will use the integrated systems to practice the launch countdown and load the rocket with the propellants it needs to send Orion on a lunar journey in preparation for launch,” Tom Whitmeyer, deputy associate administrator for Common Exploration Systems Development at NASA Headquarters in Washington, said in the post. The SLS has four liquid-propellent engines and a pair of 17-story-tall boosters that can burn close to 3 million gallons of fuel in under eight minutes—the amount of time it will take to push Orion into low Earth orbit. Those boosters give it enough heft and thrust to carry 59,500 pounds of cargo for hundreds of thousands of miles, earning it the title of a heavy-lift, deep-space rocket.

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Building the SLS has been a decade-long process for NASA and its manufacturing partners. The space agency first shared the rocket’s design with the public back in 2011. Initially, NASA had planned the maiden mission for 2017—but that date was pushed back several times due to issues with the power unit and other parts in the Orion spacecraft. If all goes well with the wet dress rehearsal, however, the vehicle could hit the launch pad for real in another few weeks.

The one downside to the system is that it isn’t completely reusable. At $23 billion, construction expenses have already exceeded the original budget; the cost per-mission is estimated to be around $2 billion. A salvageable vehicle, like SpaceX’s stainless steel Starship prototype, could fly people and payloads over long distances for far less money. But for now, NASA has its sights set on putting its most heavy-hitting rocket a little closer to the moon, and someday Mars.

See some NASA photos from the SLS launchpad rollout below.

NASA SLS rocket parts separated on a giant hydraulic lift
Teams retracted the first two of 20 platforms surrounding the SLS rocket and Orion spacecraft that allow work on the integrated system in High Bay 3 inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida. The first platforms to be retracted—which move like hydraulic kitchen drawers when moved—are those located near the launch abort system on Orion NASA/Kim Shiflett
Construction vehicle on treads moving NASA Orion spacecraft parts from a building at Kennedy Space Center in Florida
The crawler-transporter 2, driven by engineers and technicians, approaches the Vehicle Assembly Building (VAB) at Kennedy Space Center on March 11, 2022. The crawler will go inside the VAB, where it will slide under the Artemis I SLS with the Orion spacecraft atop on the mobile launcher and carry it to Launch Complex 39B for a wet dress rehearsal test ahead of the Artemis I launch. NASA/Kim Shiflett
NASA SLS rocket with Orion mounted on top at the Kennedy Space Center launch pad at night seen from above

In this view looking down in High Bay 3 of the Vehicle Assembly Building at Kennedy Space Center, the Artemis I Space SLS and Orion spacecraft can be seen without any work platforms surrounding them on March 17, 2022. NASA/Kim Shiflett
Black person with long dreads taking a selfie with a smartphone in front of the NASA SLS rocket at Kennedy Space Center in Florida
People and cars crowded the spectator zone at Kennedy Space Center on March, 17, 2022, ahead of the wet dress rehearsal, which started in the pre-dawn hours of March 18. NASA/Kim Shiflett
Full moon behind the NASA SLS rocket on the launchpad at Kennedy Space Center in Florida
The Moon is seen rising behind the SLS rocket with the Orion spacecraft aboard atop a mobile launcher as it rolls out to Launch Complex 39B for the first time, Thursday, March 17, 2022, at the Kennedy Space Center. NASA/Aubrey Gemignani

Correction (March 21, 2022): The story first incorrectly reported that the SLS rocket is more than double the height of the Saturn V. That measurement was taken from the Saturn V’s height without boosters: All together, the older rocket is actually slightly taller than the SLS.