Elon Musk's SpaceX called off its first launch attempt of its giant Starship rocket due to a technical issue, the company said.
The rocket, one of the biggest and most powerful ever built, was supposed to launch Monday morning from SpaceX's private facility in South Texas. It is designed to carry cargo and people to the moon and Mars.
The SpaceX "team is working towards next available opportunity," the company said in a statement.
Starship is the tallest rocket ever built — 394 feet tall.
It has 33 main engines — the most engines ever in a rocket booster — that can generate 16.7 million pounds of thrust at full throttle. Known as the Super Heavy booster, this part of the spacecraft accounts for 164 feet (50 meters) of its height and propels the upper rocket into orbit.
Elon Musk tweeted that a "pressurant valve" on the SpaceX appeared to be frozen and said they were standing down from today's flight test attempt.
What to know about the flight mission
SpaceX in February completed a test firing of the Super Heavy booster, in one of the final technical steps towards the launch.
The test flight was set to last 90 minutes. If all goes according to plan when the rocket does launch, the Super Heavy booster will separate from Starship about three minutes after launch and splash down in the Gulf of Mexico.
The spacecraft would continue eastward, passing over the Atlantic, Indian and Pacific oceans before ditching near Hawaii.
Starship is designed to be fully reusable but nothing will be saved from the test flight.
But with a fleet of Starships under construction at Starbase, Elon Musk estimates an 80% chance that one of them will attain orbit by year’s end. He expects it will take a couple years to achieve full and rapid reusability.
Elon Musk sets expectations low, guarantees 'excitement'
Elon Musk said at a conference last month that: “I’m not saying it will get to orbit, but I am guaranteeing excitement. It won’t be boring.” “I think it’s got, I don’t know, hopefully about a 50% chance of reaching orbit.”
Musk said over the weekend he wanted to "set expectations low" because "probably tomorrow will not be successful — if by successful one means reaching orbit."
Starship is critical to NASA’s plan to return astronauts to the moon. "The payload for this mission is information," Musk said. "Information that allows us to improve the design of future Starship builds," he added.
