Kennedy Space Center: NASA has postponed the launch of the Artemis II mission after engineers detected a disruption in the helium flow system of the Space Launch System rocket. The issue was discovered during routine checks and prompted officials to halt launch preparations to ensure astronaut safety.
The problem affects the rocket’s interim cryogenic propulsion stage, where helium is used to pressurize fuel tanks, purge engines and maintain stable propellant conditions. Engineers found that the system was not maintaining proper helium flow, making it unsafe to proceed with launch operations.
To allow full inspection and repairs, NASA is rolling the rocket back to the Vehicle Assembly Building at Kennedy Space Center. Technicians will examine the system, identify the cause of the malfunction and carry out necessary fixes before the vehicle returns to the launch pad.
The delay means the previously planned March 2026 launch window is no longer possible. NASA is now targeting April 2026 as the earliest potential launch period, though further delays remain possible depending on repair progress and testing results.
Artemis II is set to carry four astronauts on a journey around the Moon and back to Earth. The mission will be the first crewed deep space flight since 1972 and is a crucial step in NASA’s Artemis program, which aims to return humans to the lunar surface and prepare for future missions to Mars.
The mission has faced technical setbacks in the past, including hydrogen fuel leak issues detected during earlier testing. Officials emphasize that delays are expected in complex human spaceflight missions and that safety remains the highest priority.
NASA said it will provide further updates once repairs are complete and a new launch date is confirmed.