CAPE CANAVERAL, Fla. — A fuel leak and then an engine problem during final preparations for liftoff prompted NASA to halt the launch of its powerful New Moon rocket Monday morning during a flight with three test dummies on board.
The next launch attempt will take place on Friday at the earliest.
As the precious minutes ticked away, NASA repeatedly stopped and started refueling Space Launch System rocket with nearly 1 million gallons of super-cold hydrogen and oxygen due to a highly explosive hydrogen leak at the same location that saw a leak during a dress rehearsal in the spring.
Then NASA ran into a new problem when it failed to properly cool one of the rocket’s four main engines, officials said. Engineers continued to work to collect data and determine the source of the problem after the launch delay was announced.
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The rocket was supposed to lift off with a mission to put a crew capsule into orbit around the moon. The launch marks a milestone in America’s quest to return astronauts to the lunar surface for the first time since the Apollo program ended 50 years ago.
The 322-foot-long (98-meter) spacecraft is the most powerful rocket ever built by NASA, surpassing even the Saturn V that took the Apollo astronauts to the moon.
As for when NASA might attempt another launch, launch commentator Derol Nail said the issue is still being analyzed and “we’ll have to wait to see what comes out of their test data.”
There were no astronauts in the rocket’s Orion capsule. Instead, test dummies equipped with sensors to measure vibrations, cosmic radiation and other conditions were strapped in for the six-week mission, scheduled to end with the capsule’s descent into the Pacific Ocean in October.
Although there was no one on board, thousands of people jammed the shore to see the rocket lift off. Vice President Kamala Harris was expected among the VIPs.
The launch, when it happens, will be the first flight in NASA’s 21st-century lunar exploration program, named Artemis after Apollo’s mythological twin sister.
Assuming the test goes well, astronauts will board for a second flight and fly around the moon and back as soon as 2024. A two-person moon landing could follow by late 2025.
The problems seen on Monday were reminiscent of those at NASA space the shuttle era, when a hydrogen fuel leak interrupted the countdown and delayed a series of launches in the 1990s.
Later in the morning, NASA officials also spotted what they feared was a crack or some other defect on the main stage — the large orange fuel tank with four main engines on it — but later said it appeared to be just an accumulation of frost.
Launch Director Charlie Blackwell-Thompson and her team also had to deal with a communications problem involving the Orion capsule.
Engineers struggled to make sense of an 11-minute delay in the communications lines between launch control and Orion that occurred late Sunday. Although the problem was cleared up by Monday morning, NASA needed to know why it happened before committing to a launch.
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