Artemis II will fly astronauts around moon: What to know about launch

NASA's Artemis II test flight is set for Wednesday, a trip that will mark the first crewed mission to head toward the moon in more than five decades.

The launch from NASA's Kennedy Space Center on Merritt Island, Fla., is scheduled for 6:24 p.m. ET on Wednesday. The onsite countdown clock began ticking down at 4:44 p.m. ET on Monday.

With that countdown underway, engineers are powering up flight hardware, checking communication links and preparing the rocket's cryogenic systems for the precise fueling sequence required to load hundreds of thousands of gallons of super-cooled liquid hydrogen and liquid oxygen, according to a NASA release.