On March 23, 2025, NASA successfully completed a major milestone for the Artemis II mission with the integration of the core stage of the Space Launch System (SLS) rocket at Kennedy Space Center in Florida. This achievement marks another critical step toward launching the first crewed mission under NASA’s Artemis program. The successful integration was reported in a post by NASA on March 24, 2025, showcasing the steady progress of the Artemis II mission (NASA, 2025).
This integration process brought the core stage together with the solid rocket boosters, which were stacked and secured in the Vehicle Assembly Building. The core stage, measuring 212 feet in height, is a significant component of the SLS rocket, which will carry the Orion spacecraft and its crew on their 10-day journey around the Moon as part of Artemis II. The Artemis II flight will not only test the mission’s systems and hardware but also set the stage for NASA’s future deep space exploration missions, including human missions to the Moon and eventually Mars.
The Core Stage: Backbone of the SLS Rocket
The core stage of the SLS rocket is the backbone of the entire launch system, serving as the central component that supports the launch vehicle stage adapter, interim cryogenic propulsion stage, Orion stage adapter, and the Orion spacecraft. The integration of this essential component is crucial to ensuring that all parts of the mission come together seamlessly.
Using one of the five overhead cranes at Kennedy’s Vehicle Assembly Building, the team at NASA’s Exploration Ground Systems Program, along with their primary contractor Amentum, lifted the core stage and carefully placed it between the solid rocket boosters, which had already been stacked atop the mobile launcher. This was a carefully coordinated operation that required precision and expertise, with the core stage now serving as the central unit holding all other critical components for the mission.
Once in place, the core stage will be prepared for the next phase of integration, including the addition of the Orion stage adapter, which will be lifted and secured atop the core stage in the coming weeks. This step is essential to complete the structure that will support the Orion spacecraft as it journeys to the Moon.
The Artemis II Mission: Paving the Path to Deep Space Exploration
Artemis II represents the first crewed mission under the Artemis program, which aims to establish sustainable human exploration on the Moon by the mid-2020s and eventually send astronauts to Mars. Artemis II will take four astronauts on a mission that will orbit the Moon for 10 days, testing the essential hardware and systems that will support human missions to the lunar surface.
This test flight will help confirm the functionality and safety of the entire spacecraft and the launch vehicle, which will be critical as NASA moves forward with its plans for landing astronauts on the Moon. The mission’s success will provide the foundational data necessary to ensure that future human space exploration missions are not only feasible but sustainable.
The SLS rocket and Orion spacecraft are central to NASA’s vision for deep space exploration, and the integration of these critical components is just one step in the journey to send astronauts beyond low-Earth orbit. The Artemis II mission is particularly important because it will test the spacecraft’s performance in deep space and provide the first opportunities to evaluate human spaceflight beyond the Earth-Moon system.
What’s Next for Artemis II
Now that the core stage integration is complete, the next steps involve further assembly and integration of the remaining components. The next significant task will be the addition of the Orion stage adapter, which will support the Orion spacecraft during launch. Following this, the rocket will undergo a series of tests to ensure that all systems are operating correctly before the launch.
NASA engineers and ground systems teams will continue to work meticulously to prepare the spacecraft and rocket for flight. These preparations include finalizing the integration of the cryogenic propulsion stage, performing engine tests, and ensuring the performance of the SLS rocket’s key systems. Once these steps are completed, the Artemis II mission will be ready for launch, marking a monumental step in humanity’s efforts to return to the Moon and beyond.