www.nasa.gov

OCTOBER 2020 – JANUARY 2021

SPACE LAUNCH SYSTEM

National Aeronautics and

Space Administration

BOOSTERS 

STACK UP 

AT KENNEDY
ARTEMIS I LAUNCH PREP 

STACKS UP

The Space Launch System solid rocket boosters are being stacked on the mobile launcher in the Vehicle Assembly Building at Kennedy Space 

Center in preparation for the Artemis I launch. Together, the twin boosters provide more than 75 percent of the total SLS thrust at launch.

NASA is stacking the first part of the Space Launch System rocket on the mobile launcher in preparation for the Artemis I launch. 

In November, engineers at NASA’s Kennedy Space Center lowered the first of the SLS solid rocket booster segments on the mobile 

launcher in the Vehicle Assembly Building. The boosters are the first components of the rocket to be installed on the launcher and 

will help support the remaining rocket pieces and the Orion spacecraft. To stack the remaining booster segments, crews are using 

an overhead crane that can hold up to 325 tons (the weight of about 50 elephants) to lift each segment for mating. Each motor 

segment weighs about 300,000 pounds, or 150 tons. When fully assembled, each booster will stand 177 feet tall, taller than the 

Statue of Liberty from base to torch.

When the deep space rocket launches on the Artemis I mission later this year, the boosters will provide more than 75 percent of 

thrust for the liftoff from Launch Pad 39B.

Read more about how the SLS boosters are stacked: go.nasa.gov/3bXSPVM
GREEN RUN TEST FIRES UP 

ALL FOUR SLS ENGINES

The four RS-25 engines in the SLS core stage ignite 

during the Jan. 16 test at NASA’s Stennis Space 

Center. The engines fired for a little over a minute and 

generated 1.6 million pounds of thrust.

The core stage for the first flight of NASA’s Space Launch System rocket is seen in the B-2 Test Stand at Stennis Space Center during a Jan. 16 

hot fire test. The hot fire test included loading 733,000 gallons of liquid oxygen and liquid hydrogen – mirroring the launch countdown procedure 

– and igniting the engines.

NASA’s Space Launch System program started the new year with a milestone as the core stage that will fly on the Artemis I 

mission fired up all four engines together for the first time. 

The Jan. 16 test was the eighth test of the Green Run Test Series at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. 

The test plan called for the rocket’s four RS-25 engines to fire for a little more than eight minutes – the same amount of time it 

will take to send the rocket to space following launch. The team successfully completed the countdown and ignited the engines, 

but the engines shut down a little more than one minute into the hot fire. The Green Run team has reviewed extensive data and 

completed preliminary inspections that show the core stage is in excellent condition, and NASA plans to conduct a second 

Green Run hot fire test as early as the fourth week of February.

The agency's goal for the hot fire was to support 23 detailed verification objectives using data acquired from the this test combined 

with analysis and testing that has already been completed. These detailed verification objectives are used to certify the design of 

the SLS rocket’s core stage. The preliminary assessment indicates that the data acquired met the goals for a number of the 23 

objectives, such as those related to activities prior to engine ignition. The initial assessment also indicates that data acquired 

partially met the goals for several additional objectives related to simultaneous operation of the four RS-25 engines.

NASA and its industry partners, Boeing and Aerojet Rocketdyne, assessed the data from the test and determined that a 

second, longer hot fire test should be conducted and would pose minimal risk to the core stage. The second test is planned for 

the fourth week of February.

Read the latest updates on SLS progress: go.nasa.gov/3jdCNbK
DESPITE PANDEMIC, STORMS, 

ARTEMIS FLIGHT PREP MAKES 

PROGRESS IN 2020

In 2020, NASA and the SLS program pressed forward during challenges brought by the COVID-19 pandemic and multiple tropical storms. 

Despite the hurdles, SLS teams made significant progress toward launch, achieving a number of significant milestones. Here are the top 

stories from the past year.

ARTEMIS I CORE STAGE 

DELIVERED FOR GREEN 

RUN TESTING

The Artemis I core stage was delivered from Michoud Assembly 

Facility to Stennis Space Center for the Green Run 

series of tests to validate the stage’s design. The eight-part 

series steadily brought the new, or “green,” core stage flight 

hardware to life for the first time, culminating in a hot fire of the 

stage’s four RS-25 engines. 

Let more: go.nasa.gov/39liaHr

THE ‘WORM’ RETURNS

The iconic NASA “worm” logo will be along for the ride on the 

Artemis I mission. Teams at Kennedy Space Center applied the 

historic logo on visible parts of the rocket’s solid rocket boosters 

and the Orion spacecraft. The “worm” was first introduced by 

NASA in 1975 and was incorporated into many of the agency’s 

next-generation programs before being retired in 1992. 

Read more: go.nasa.gov/2KSH6Na
STRUCTURAL TESTING 

CAMPAIGN WRAPS UP

In June, engineers at Marshall Space Flight Center completed 

the SLS rocket’s structural testing campaign with a final “test 

to failure” of the liquid oxygen (LOX) tank test article, shown 

above. The test campaign included test articles identical in 

structure to those used in flight, including LOX tank, liquid 

hydrogen (LH2) tank, intertank, engine section, and an 

integrated test of the upper stage – the interim cryogenic 

propulsion stage (ICPS), Orion stage adapter, and the 

launch vehicle stage adapter (LVSA). The three-year test 

campaign delivered 199 test cases and 421 gigabytes of data 

to validate that the rocket’s structure is designed to endure 

the rigors of spaceflight. 

Read more: go.nasa.gov/3c2HV0U

LAUNCH VEHICLE STAGE 

ADAPTER DELIVERED TO 

KENNEDY

The launch vehicle stage adapter (LVSA) was delivered to 

Kennedy Space Center in July. The LVSA connects the 

rocket’s core stage to the upper stage and helps protect the 

RL10 engine that will provide the power necessary to send the 

Orion spacecraft on its journey to the Moon. 

Read more: go.nasa.gov/3qLgjBG

BOOSTER TESTING FOR 

THE FUTURE

On Sept. 2, the SLS Boosters Office and prime contractor 

Northrop Grumman fired up a solid rocket booster to evaluate 

materials and processes to improve booster performance on 

missions after Artemis III. The full-scale booster test, conducted 

at Northrop Grumman’s test facility in Promontory, Utah, lasted 

a little over two minutes, the same amount of time that the 

boosters power the SLS rocket during liftoff and flight. 

Read more: go.nasa.gov/3iBK4SB

BOOSTERS SHIPPED 

FOR STACKING

The 10 motor segments for the SLS rocket’s two solid rocket 

boosters were shipped in June to Kennedy Space Center to 

be stacked for the Artemis I launch. The segments traveled 

by rail on a 10-day journey from Northrop Grumman’s booster 

manufacturing facility in Promontory, Utah, to Florida. NASA’s 

Exploration Ground Systems teams are working to process 

the segments and have begun stacking them on the mobile 

launcher in preparation for flight. 

Read more: go.nasa.gov/3pa6m0b
LAUNCH CONTROL 

READIED FOR ARTEMIS I

It’s not just the SLS rocket’s hardware that undergoes extensive 

testing before flight. The systems and crews charged with 

ensuring a safe launch are also trained and tested. The Core 

Stage Green Run series of tests at Stennis Space Center 

included a simulation of the launch sequence, validating the 

timeline and sequence of events leading up to firing of the four 

RS-25 engines. At Kennedy Space Center, the Exploration 

Ground Systems team of launch controllers who will oversee 

the countdown and liftoff of the SLS rocket and Orion 

spacecraft have conducted simulations to hone the team’s 

skills by rehearsing anomalies and other unexpected situations 

that controllers and launch managers must solve in real-time 

during a launch. 

Read more: go.nasa.gov/3cbBXuA

SLS EXPLORATION 

UPPER STAGE COMPLETES 

DESIGN REVIEW

On Dec. 18, a team of NASA, Boeing, and independent 

reviewers certified the SLS Exploration Upper Stage (EUS), the 

evolved configuration of the SLS rocket’s upper stage, meets 

requirements for future missions. The EUS replaces the ICPS 

on the SLS Block 1B rocket. The larger, more powerful EUS will 

be able to transport 40 percent more payload to the Moon than 

the ICPS. 

Read more: go.nasa.gov/3sWhm3r

ARTEMIS ASTRONAUT 

TEAM ANNOUNCED

On Dec. 9, NASA announced it has selected 18 astronauts from 

its corps to form the Artemis Team and help pave the way for the 

next astronaut missions on and around the Moon. Five astronauts 

were present at the announcement made during the National 

Space Council Meeting at Kennedy Space Center. From left, 

astronauts Jessica Meir, Joseph Acaba, Jessica Watkins, 

Matthew Dominick, and Anne McClain answer questions from 

news media during the announcement. 

Learn more about the Artemis Team: go.nasa.gov/3a6ZxWG

NASA BUILDING CORE 

STAGES FOR ARTEMIS II 

AND ARTEMIS III 

While the core stage for the Artemis I SLS flight undergoes 

final testing, stages for the Artemis II and Artemis III missions 

are well into production. At Michoud Assembly Facility in New 

Orleans, the main core stage structures for the Artemis II 

mission have been built (including the intertank above) and are 

being outfitted with electronics, feedlines, propulsion systems, 

and other components. Engineers are welding the core stage 

structures for the Artemis III mission, which will land the first 

woman and the next man on the lunar surface. 

Read more: go.nasa.gov/3oiLqmu
CORE STAGE GREEN RUN, EXPLAINED 

WHAT’S NEW IN SLS SOCIAL MEDIA

Why is the SLS core stage orange? What happens during Green Run testing? Lisa Bates, NASA SLS Stages Green Run manager 

(left), answers viewer questions during a Facebook live broadcast. Watch the video here: bit.ly/39RqleP

STACKING THE BOOSTERS FOR LAUNCH

At Kennedy Space Center, the SLS solid rocket boosters are stacking up in preparation for flight. Dave Diaz, Integrated Operations 

Manager for NASA’s Exploration Ground Systems, answered questions about SLS booster stacking operations during a Facebook 

live broadcast. Watch a replay: bit.ly/3rngi77
SLS ON THE VIRTUAL ROAD

The SLS Program is committed not only to building the world’s most powerful rocket, but also to inspiring a new generation of 

scientists, engineers, and explorers. During a time when most events have become virtual, SLS subject matter experts and industry 

partners have brought news of the rocket’s progress and upcoming Artemis missions to a range of audiences, from schools to 

science centers to government organizations. One plus to the virtual environment: You don’t need to travel to get the latest SLS news. 

Click here to view the most recent updates (some presentations may require free registration): go.nasa.gov/3oVYY7A

The SLS Program continues to share the SLS and Artemis stories in virtual events. Maury Vander, chief of test 

operations at Stennis Space Center, talks to the Louisiana Art & Science Museum. 

Dawn Stanley, Deputy Director of Cross-Program Strategic 

Integration for Exploration, speaks to students in the First 

Scholars Program at the University of Memphis. 

SLS Strategic Communications Deputy Manager Trey Cate 

gives a presentation on Doing Business with NASA: The Artemis 

Program for the National Association of Counties. 
SPACEFLIGHT 

PARTNERS: 

AMRO 

Fabricating Corp.

WHAT THEY DO FOR SLS:

Founded in 1977, AMRO is a leading 

supplier of precision machined parts, 

major assembly tooling, and ground 

support equipment. The company 

machines and forms the structural panels 

for the primary structure of the LVSA. 

AMRO also heat ages and oversees 

the final non-destructive evaluation, 

chemical film coating, and priming of the 

panels before they are delivered to prime 

contractor Teledyne Brown. Additionally, 

AMRO machined the forward and 

intermediate rings for the Artemis II and 

Artemis III adapters. 

LOCATION: South El Monte, California

NUMBER OF EMPLOYEES: 76

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