All Four RS-25 Engines Added to NASA’s Artemis II Moon Rocket Core Stage

Engineers and technicians from NASA, Aerojet Rocketdyne, and Boeing at NASA’s Michoud Assembly Facility in New Orleans have installed all four RS-25 engines to the core stage for NASA’s Space Launch System rocket that will help power the first crewed Artemis mission to the Moon. The yellow core stage is seen in a horizontal position in the final assembly area at Michoud. The engines are arranged at the bottom of the rocket stage in a square pattern, like legs on a table. Credit: NASA/Eric Bordelon

NASA has successfully attached all four RS-25 engines to the Artemis II Moon rocket’s core stage. This milestone is a part of NASA’s Artemis program, aiming to land the first woman and person of color on the Moon.

Teams at NASA’s Michoud Assembly Facility in New Orleans have structurally joined all four RS-25 engines onto the core stage for NASA’s Artemis II Moon rocket. The flight test is the agency’s first crewed mission under Artemis.

Technicians added the first engine to NASA’s SLS (Space Launch System) rocket core stage on September 11. Teams installed the second engine onto the stage on September 15 with the third and fourth engines on September 19 and September 20. Technicians with NASA, Aerojet Rocketdyne, an L3Harris Technologies company and the RS-25 engines lead contractor, along with Boeing, the core stage lead contractor, now will focus efforts on the complex task of fully securing the engines to the stage and integrating the propulsion and electrical systems within the structure.

We need the biggest rocket stage ever built for the bold missions in deep space that NASA’s Space Launch System rocket will give us the capability to achieve. This infographic sums up everything you need to know about the SLS core stage, the 212-foot-tall stage that serves as the backbone of the most powerful rocket in the world. The core stage includes the liquid hydrogen tank and liquid oxygen tank that hold 733,000 gallons of propellant to power the stage’s four RS-25 engines needed for liftoff and the journey to Mars. Credit: NASA/MSFC

Core Stage: The Heart of Artemis II

The SLS core stage, at 212 feet, is the backbone of the Moon rocket. Its two huge propellant tanks provide more than 733,000 gallons of super-chilled liquid propellant to the four RS-25 engines, while the stage’s flight computers, avionics, and electrical systems act as the “brains” of the rocket. During Artemis II, the RS-25 engines will together provide more than 2 million pounds of thrust for eight minutes of flight, helping to send the Artemis II crew beyond low-Earth orbit to venture around the Moon.

NASA’s Ambitious Moon Mission

NASA is working to land the first woman and first person of color on the Moon under Artemis. SLS is part of NASA’s backbone for deep space exploration, along with Orion and the Gateway in orbit around the Moon, and commercial human landing systems. SLS is the only rocket that can send Orion, astronauts, and supplies to the Moon in a single mission.