The main issue being that one of the main engines did not adjust to the right temperature needed to launch.
"I am very proud of this launch team. They have solved several problems along the way and they got to one that needed time to be solved," said NASA administrator Bill Nelson.
NASA partnered with several companies to build and construct the Artemis 1 rocket and the company tasked with manufacturing those big RS-25 engines (seen on the bottom of the rocket) is Aerojet Rocketdyne.
They were manufactured in Southern California at the Canoga Park campus.
"We've got to make sure those engines are ice cold. And they were seeing readings that indicated that one of the engines wasn't getting as cold as they expect it to. That's what we call an anomaly," said Aerojet Rocketdyne program management specialist Samantha Fuchs.
The engine issue might've concerned viewers tuning in, but Fuchs says scrubbing a launch isn't uncommon.
Aerojet Rocketdyne had been building rocket engines for various space missions for decades. The company had 16 RS-25 engines needed to launch Artemis 1 before the project began.
The ones attached to the rocket today have been on other missions in the past.
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"We have a contract with NASA to really modernize these engines and make them more affordable over time," Fuchs said.
They've created engines that contributed to the Apollo program, engines that have launched satellites into space. Plus, the Redstone A7 engine which helped launch Alan Shepard into orbit, the first American to space travel.
This Artemis flight will be the first in NASA's Artemis project, the goal is to eventually put astronauts back on the moon, which hasn't been done in 50 years since the Apollo program.
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