BREVARD COUNTY, Fla. — A critical test is expected to happen for the Artemis I mission in the next 48 hours.

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Teams need to make sure the massive moon rocket and Orion spacecraft are ready for launch, and workers have fixed a troublesome hydrogen leak.

The call to stations began Monday afternoon. The launch team plans to load the SLS core stage and the interim cryogenic propulsion stage with super-cold liquid oxygen and liquid hydrogen to confirm the hydrogen leak that scrubbed the last launch attempt has been repaired.

READ: NASA announces 2 potential launch windows for Artemis I

Later this week, ahead of the agency’s next launch attempt, the replacement seals will be tested under the same conditions that the systems will experience on launch day.

“We’ve gone through a number of operations with this vehicle; we’re learning more about this vehicle,” said Tom Whitmeyer, NASA’s deputy associate administrator for the Common Exploration System. “It’s a new machine for us. Of the things I think we have a better appreciation for now and what we’ll be demonstrating on Wednesday is what we call kinder and gentler loading operations.”

READ: NASA to conduct test on mega moon rocket to see if technical issues are fixed

NASA officials said they were working toward a launch attempt as early as Sept. 27.

TIMELINE: NASA scrubs launch of Artemis I due to technical issues with engine

Video: NASA to conduct test on mega moon rocket to see if technical issues are fixed NASA crews are preparing for an important test for its Artemis I mission. (James Tutten, WFTV.com/WFTV)

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