NASA cancelled a second attempt on Saturday (Sept. 3) to launch its new 30-story rocket and send an uncrewed test capsule to the Moon after engineers discovered a fuel leak.
As millions of people around the world and hundreds of thousands on nearby beaches awaited the historic launch of the massive Space Launch System (SLS)
a leak near the rocket's base was discovered as ultra-cold liquid hydrogen was being pumped in.
"Today's Artemis I launch has been cancelled by the launch director," NASA said in a statement. "Multiple troubleshooting efforts to address the leak area... did not resolve the issue."
an estimated 400,000 people gathered nearby to see - and hear - NASA's most powerful vehicle ever launched climb into space.
The initial launch attempt on Monday was also cancelled after engineers discovered a fuel leak and a sensor revealed that one of the rocket's four main engines was overheating.
Launch director Charlie Blackwell-Thompson gave the go-ahead to begin filling the rocket's tanks with cryogenic fuel early Saturday.