Artemis II Rocket Rolled Back to Vehicle Assembly Building for Helium Issue Troubleshooting

NASA is rolling back the Space Launch System (SLS) rocket and Orion spacecraft for the Artemis II mission to the Vehicle Assembly Building (VAB) at the Kennedy Space Center in Florida. This decision comes after an interruption of helium flow in the SLS’ upper stage was detected on February 21, 2026.

Rollback Details

The rollback began approximately 9 a.m. EST on Wednesday, February 25, 2026, and is expected to take up to 12 hours as the rocket travels the four-mile distance atop the Crawler-Transporter 2 vehicle [NASA]. This action removes the March launch window from consideration.

Background on Artemis II

The Artemis II mission aims to send four astronauts – NASA’s Reid Wiseman, Victor Glover, and Christina Koch, and Canadian Space Agency’s Jeremy Hansen – on a 10-day trip around the Moon and back to Earth [Kennedy Space Center Visitor Complex]. This will be the first crewed mission beyond low Earth orbit since the Apollo 17 mission in 1972.

Previous Testing and Issues

The SLS rocket and Orion spacecraft were initially rolled out to Launch Pad 39B on January 17, 2026. A wet dress rehearsal was conducted between February 18-19, 2026, successfully completing the procedures leading up to launch. Prior to this, a liquid hydrogen propellant leak during a wet dress rehearsal on February 2, 2026, required seal replacements [Space.com].

Future Launch Windows

With the March launch window closed, NASA is now considering launch opportunities beginning April 1, with additional opportunities between April 3-6 and on April 30 [Space.com].

About Artemis

The Artemis program represents NASA’s effort to return humans to the Moon, with the ultimate goal of establishing a long-term presence and paving the way for future exploration [NASA].