Artemis I Path to the Pad: The Most Powerful Rocket NASA Has Ever Built

All of the components that make up the rocket's boosters were created by Northrop Grumman in Promontory, Utah, where the process began.

The booster segments were brought to Kennedy Space Center's Rotation, Processing, and Surge Facility, or RPSF, after a 10-day cross-country trip. If anything seems similar, it's because the processing of the shuttle booster segments, which all originated in Utah, was done at the same site.

The rest of the motor segments are then put together and placed on top of the mobile launcher as they prepare to enter the famed Vehicle Assembly Building, or VAB.

The one thing about this car, of course, is that it is made all throughout the nation. All of the elements arrive here. Although they may be produced all throughout the country, the Vehicle Assembly Building is where they are all assembled.

8.8 million pounds of thrust will be produced by our SLS rocket in order to overcome the gravitational pull of the Earth. The Space Shuttle and the Saturn V rocket both utilized more power than that.

The boosters that will hold the majority of that power are being put together by teams from NASA's Exploration Ground Systems. The ten motor segments that make up the twin solid rocket boosters' total height when fully stacked will be close to 17 stories.

Teams first examine and prepare the hardware. They are now prepared to begin stacking the segments, which requires time, patience, and a steady hand.

When everything in High Bay 4 is finished, we use a 325-foot crane to take up the segment and move it to where it is today, over the 16th-floor crossover, and then we start stacking the segments. Each segment is lifted and stacked over the crossover on the sixteenth floor. Once stacked, each section is placed on top of the one beneath it, and the entire structure is then secured with 177 pins, one for each segment.

The team's nerves may also be put to the test by the pressure to do the task flawlessly.

Processing flight hardware in this way entails a great deal of responsibility. Sometimes it makes me nervous, but it's exciting. A software like this has no tolerance for danger.

A group of shuttle crew members are with us to guide the route. They are there to help us if we get lost. It was really nerve-wracking at first when stacking. A small amount of the nerve is lost with each piece we layered. By the third or fourth one, everything is simple. We're persevering, the anxiety has subsided, and we're simply eager for it to be over.

Now that all 10 booster segments are fully stacked on the mobile launcher, the core stage is the last component needed to complete the power needed to launch SLS into space.

The SLS core stage, the NASA Pegasus barge, traveled 900 miles to get there.

Kennedy Space Center now houses the biggest rocket stage NASA has ever constructed.

It's a big day today. This is the final significant piece of hardware required for Artemis 1's intensive processing. And we've only been impatiently awaiting the arrival of this component of the vehicle so that we could begin the subsequent stages of our stacking activities.

The core stage traveled all the way from Mississippi's Stennis Space Center, measuring a towering 212 feet tall and weighing a massive 188,000 pounds. The core stage underwent numerous rounds of demanding testing, such as what is referred to as its Green Run series, which really put its performance to the test.

Eight rounds of the series, which examined each system separately before reaching pure power, were engaged. The core stage's RS-25 engines fired for eight minutes nonstop during the successful final test, which resulted in nearly 700,000 gallons of propellant pouring through it.

And that triumph was not achieved without facing certain obstacles, demonstrating why NASA tests so frequently and rigorously.

On the first hot-fire test, we actually conducted a one-minute test from which we learned a lot. We improved our understanding of the vehicle, made a few adjustments, and resumed our second hot-fire test.

Being able to work through that process and finish it brought about a lot of delight, craftsmanship, and ownership. It was sheer elation when we attempted to put out the second hot fire for 500 seconds.

Teams transported the core stage into the VAB once it arrived at Kennedy, where it was raised by a crane and positioned between the twin solid rocket boosters.

The core stage, which acts as the rocket's foundation, will produce more than 2 million pounds of thrust to assist in launching the Orion spacecraft on its orbital mission around the Moon.

We basically pick two points at the end of the core stage, one on the back portion of it and one on the front portion of it, lift it up to the point where we can change it from a horizontal position over into a vertical position, and then transport it all the way to the top of the Vehicle Assembly Building and cross it over into High Bay 3, where we make sure that it is properly aligned.

With the twin boosters now fully assembled, NASA's biggest rocket stage is prepared to launch Orion into space. To provide the capsule the extra thrust it needs to travel tens of thousands of kilometers beyond the Moon, however, would require one more crucial component.

The interim cryogenic propulsion stage, or ICPS, will deliver more than 20,000 pounds of thrust to launch Orion on a once-in-a-lifetime journey with just one RL10 engine.

Teams then attached the launch vehicle stage adapter to the core stage, then the ICPS, to connect it with the rocket stack.

In essence, the ICPS, or interim cryogenic propulsion stage, is the upper stage of the entire SLS vehicle. The Orion capsule and the service module will next be propelled toward their target, which at this time will be the Moon.

However, before the spacecraft is joined to the rocket, crews will carry out a number of tests to make sure all of SLS's components, as well as the ground systems equipment, the Launch Control System, and its software, interact with one another effectively.

The fact that those testing techniques have evolved greatly since the Apollo Program exacerbates the difficulty.

The Vacuum Assembly Building (VAB) was initially constructed in the 1960s to house the assembly of the Saturn V, the largest rocket ever built by humans for the Apollo missions to the Moon. Since then, the VAB has undergone significant modifications to support a variety of rockets and spacecraft, whether they are traveling to low-Earth orbit or exploring deep space.

This high bay was used by the Shuttle. It had been an Apollo legacy before then. Upgrades, including those that will support Artemis II and Artemis III, are still being made today.

Orion won't be the only thing SLS launches into orbit as it lifts off from Kennedy Space Center's Launch Pad 39B. Small, shoebox-sized satellites known as CubeSats that were loaded into the Orion stage adapter in Kennedy's Space Station Processing Facility are traveling with Orion.

The extra capacity in the stage adapter offers a once-in-a-lifetime chance to launch those CubeSats to deep orbit for independent scientific and research missions.

These CubeSats are available to study a variety of subjects, including the Moon, asteroids, and the impact of space radiation on living things.

The spacecraft itself, which has been at the Launch Abort System Facility getting outfitted with one of the spacecraft's most essential elements, is the only thing left to finish the stack at this time.

The launch abort system, which resembles the solid rocket motor with a sharp tip at the top of Orion, is a crucial component because it safeguards the crew in the event of an emergency. Overnight, the Orion spacecraft steadily moves toward the VAB with its launch abort mechanism fully installed.

Teams gently raise and lower it onto the Orion stage adapter as it arrives. The world's most potent rocket has now been successfully stacked, and what a sight it is to witness.

When the Shuttle is retired, how will exploration look like in the future? Do you know what our country wants to do? Where are we headed? How would you like us to explore?

It's incredible to see how far things have come from the time when people only had words and ideas in their heads to the three programs we have today, the Artemis mission, and all the hardware that has been manufactured in factories run by large aerospace companies to small mom-and-pop shops all over the nation and the world. Simply put, I'm quite proud.

A series of experiments within the VAB are necessary before SLS and Orion can usher in a new era of space exploration for our country. These tests will validate the rocket and spacecraft as an integrated system and prepare us for the last and most important milestone: wet dress rehearsal.

The launch team will be able to go through a full launch countdown and ignite the engines during the full test of the 322-foot-tall, fully integrated rocket at Launch Pad 39B.

When it leaves the VAB, I think we'll be extremely proud of it. Since it's such a significant occasion, I anticipate shedding a few tears. To get to the day of rolling out, we put in a lot of effort. Because it's the result of so much hard work from everyone, I'll probably be sobbing when we launch it and watch it through my tears.

We owe what we're doing here for the development of science, research, and technology. And this is a great chance for the United States to take back the lead in human space flight and exploration.

History is going to include Artemis significantly. When it takes off, it will unquestionably revolutionize the space sector.

This project will visit the moon. It will travel to Mars. We require that. This nation requires that. That's what the world needs.

I'm overjoyed. Even though we have a lot of work ahead of us, Artemis I will surprise everyone.

By NASA