NASA Finds New Issue That Could Delay Artemis II Mission

Engineers preparing for possible rollback as helium flow problem threatens March launch window.

Feb. 21, 2026 at 4:20pm

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NASA has discovered an issue with the helium flow in the upper stage of the Space Launch System rocket, prompting engineers to prepare for a potential rollback and threatening the March launch window for the Artemis II mission.

Why it matters

The Artemis II mission is a crucial step in NASA's Artemis program, which aims to return humans to the Moon. Any delays could push back the timeline for future Artemis missions and impact NASA's ambitious goals for lunar exploration.

The details

The issue was discovered during pre-launch testing, and NASA engineers are now working to address the helium flow problem. A rollback to the Vehicle Assembly Building would be required to access and fix the issue, which could jeopardize the planned March launch window.

  • NASA discovered the helium flow issue during pre-launch testing in February 2026.

The players

NASA

The United States National Aeronautics and Space Administration, the federal agency responsible for the country's civilian space program, aeronautics, and space research.

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What’s next

If the issue cannot be resolved in time, NASA may need to delay the Artemis II mission to a later launch window.

The takeaway

This helium flow problem highlights the technical challenges and complexities involved in preparing a massive rocket like the Space Launch System for launch, underscoring the importance of thorough testing and problem-solving to ensure mission success.