NASA has postponed its Artemis-2 lunar mission after engineers detected a mechanical fault in the Space Launch System (SLS) rocket during final preparations. The mission, originally scheduled for early March, was intended to send four astronauts around the far side of the Moon and return them to Earth after ten days. It would have been humanity’s longest-distance space journey in over fifty years.

According to NASA Administrator Jared Isaacman, the issue was found in the helium flow system, which is essential for pressurizing the rocket’s fuel tanks and cooling systems. The problem emerged after a 50-hour test that had shown no faults, leading the team to believe the launch could proceed by March 6. NASA described the helium insufficiency as a serious technical problem requiring further maintenance.

On February 19, the rocket had been fueled with about 730,000 gallons of propellant, marking a major milestone in launch preparation. NASA hopes that resolving the issue will allow the Artemis-2 mission to proceed successfully, paving the way for Artemis-3, which aims to land astronauts on the Moon for the first time since 1972.