Technicians are preparing to connect two major parts of the Space Launch System (SLS) rocket’s Artemis II core stage.
On Jan. 30, technicians moved the largest part of the stage, the 130-foot liquid hydrogen tank to the vertical assembly area at NASA’s Michoud Assembly Facility. Here, it will be prepared for joining with the 66-foot forward assembly.

The forward assembly comprised of the joined forward skirt, intertank, and liquid oxygen tank completed construction and was transported to the final assembly area inside the factory on Jan. 10. Technicians will move the liquid hydrogen tank back to this final assembly where Boeing, the lead core stage contractor, will join the two structures. This will complete construction of most of the core stage that will launch the first crew on the Artemis II mission.

Only the engine section, the fifth piece of the stage, will need to be added to complete the Artemis II core stage. The engine section is one of the most complex parts of the stage. It includes the main propulsion system that connects to the four RS-25 engines that are built by Aerojet Rocketdyne and are assembled and stored at their facility at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. The engines will be the last items installed on the stage. During launch, more than 700,000 gallons of propellant flows from the core stage tanks to the engines that produce more than 2 million pounds of thrust to help launch the SLS rocket.

The core stage serves as the backbone of the rocket, supporting the weight of the payload, upper stage, and Orion crew vehicle, as well as the thrust of its four RS-25 engines and two five-segment solid rocket boosters attached to the engine and intertank sections. The Artemis II mission will help NASA prepare for later Artemis missions that will enable the first woman and first person of color to land on the Moon.

Image Credit: NASA/Jared Lyons