SpaceX has aborted the latest launch of Starship in what was set to be a crucial test of the Mars-bound rocket. The lift off of the 123-metre-tall rocket, which is the biggest rocket ever built, was scrubbed just before 6pm local time (12am GMT) on Monday at SpaceX’s Starbase facility in Texas.

SpaceX delayed the Starship rocket test flight due to an unspecified issue. The launch, aimed at furthering Mars colonization, was to occur from Texas. A reschedule is expected within 24 hours. The rocket requires improvements for reliability and safety before future crewed missions.

Elon Musk wants the ISS deorbiting to happen as soon as possible, and he suggests that humans go to Mars next.