NASA Completes Stacking of Artemis II Solid Rocket Boosters Ahead of Crewed Lunar Mission

NASA’s Artemis II mission has reached a significant milestone as engineers at Kennedy Space Center (KSC) in Florida have successfully completed the stacking of the twin solid rocket boosters (SRBs) for the Space Launch System (SLS) inside the Vehicle Assembly Building (VAB).

The achievement marks a crucial step in preparing for the agency’s first crewed Artemis flight, a mission that will send four astronauts on a 10-day journey around the Moon.

A Step Toward Artemis II Launch

The towering boosters, each standing 177 feet tall, will generate the majority of the 8.8 million pounds of thrust needed to propel the SLS rocket and Orion spacecraft off the launch pad.

The process of stacking these boosters, which began on November 20, 2024, involved precise and carefully coordinated operations. Technicians utilized a massive overhead crane to lift and position each segment onto Mobile Launcher 1, the 380-foot-tall structure that supports and facilitates the assembly and launch of the Artemis missions.

With the final stacking of the forward assemblies—the nose cone sections of each booster—NASA engineers have now completed the full booster configuration. Each forward assembly houses critical components, including an aerodynamic top, a forward skirt containing avionics, and a frustum housing small motors that allow the boosters to detach from the SLS core stage after liftoff.

Transport and Stacking Operations

The booster stacking process required meticulous planning and execution. The ten segments, five for each booster, were transported from Kennedy’s Rotation, Processing and Surge Facility, where they underwent processing following their arrival at the space center in September 2023.

These segments were delivered by train from Northrop Grumman’s manufacturing facility in Utah, where they were initially cast and prepared for integration.

Once inside the VAB, engineers carefully stacked each segment atop the booster aft assembly, aligning them precisely to ensure structural integrity and proper performance during launch.

The final step involved adding the forward assemblies, bringing the boosters to their full height and completing the stacking sequence.

Next Up: Core Stage Integration

With the boosters now fully assembled, NASA engineers will turn their attention to integrating the SLS core stage, which is currently undergoing processing in High Bay 2 of the VAB.

In the coming weeks, the core stage will be moved into position and connected to the boosters, forming the backbone of the powerful SLS rocket.

Once the Interim Cryogenic Propulsion Stage (ICPS) and Orion spacecraft are stacked, the Artemis II launch vehicle will be fully assembled and ready for final checkouts ahead of rollout to Launch Complex 39B.

NASA’s First Crewed Mission Under ArtemisNext Up: Core Stage Integration

Artemis II represents a historic milestone in NASA’s Artemis campaign, marking the first time astronauts will travel beyond low Earth orbit since the Apollo program.

The four-person crew includes NASA astronauts Reid Wiseman, Victor Glover, and Christina Koch, along with Canadian Space Agency (CSA) astronaut Jeremy Hansen. This mission will test Orion’s life support systems and pave the way for future crewed lunar landings under Artemis III and beyond.

Through the Artemis program, NASA aims to establish a sustainable human presence on the Moon, enabling scientific discoveries, advancing economic opportunities, and laying the groundwork for the first human missions to Mars. The successful stacking of the Artemis II boosters is a vital step toward achieving these long-term exploration goals, bringing humanity closer to returning to the Moon and venturing deeper into space.