Artemis II Launch Delayed After NASA Detects Helium Flow Issue

NASA has postponed the Artemis II mission after a technical problem was found during overnight operations, affecting preparations for a crewed lunar flyby.

On February 21, 2026, NASA reported a disruption in the supply of helium to the upper stage of the Space Launch System rocket intended for Artemis II. The issue was detected during routine activities at Launch Complex 39B and required immediate attention to prevent further complications.

Helium is a critical component for the upper stage, as it is used to purge the engines and maintain pressure in the liquid hydrogen and liquid oxygen tanks. Without proper helium flow, these systems cannot operate safely or effectively during launch procedures.

To address the problem, NASA is preparing to move both the Artemis II rocket and the Orion spacecraft from their launch pad back to the Vehicle Assembly Building. This rollback is necessary to allow technicians to access and repair the affected systems.

What the numbers show

• The helium flow interruption was detected on February 21, 2026
• The Artemis II crew includes three NASA astronauts and one Canadian astronaut
• The next available launch window is in April 2026

NASA Administrator Jared Isaacman stated that the required rollback will almost assuredly remove the possibility of launching Artemis II in March. This adjustment to the schedule was confirmed as the agency assessed the time needed for repairs and safety checks.

The Artemis II mission is designed to send four crew members around the Moon and return them safely to Earth. This mission represents the next step in NASA's ongoing lunar exploration efforts and involves international collaboration with the Canadian Space Agency.

Following the detection of the helium issue, NASA confirmed that the earliest feasible opportunity to launch Artemis II will be in April 2026. The agency continues to monitor the situation and is focused on ensuring all systems are fully operational before proceeding with the mission.

NASA has not announced a specific date for the new launch attempt but indicated that further updates will be provided as repair work progresses and the rocket is readied for its next rollout to the launch pad.

* This article is based on publicly available information at the time of writing.