The crew of Integrity are about to reach the furthest distance that any human has ever been from the Earth.
Over the last few days, Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen have been making their way to their rendezvous with the Moon - the first mission of its kind since 1972.
Aside from a couple of minor technical issues, the flight has so far gone very smoothly and the crew are now eager to earn their place in the history books as their historic flyby approaches.
In just a few hours, Integrity will pass behind the Moon, reaching a distance exceeding that achieved by the crew of Apollo 13 which reached a distance of 248,655 miles from Earth in 1970.
The Artemis II crew will have an opportunity to capture some impressive photos of the Moon before the spacecraft swings around and begins its multi-day journey back home.
The flyby is expected to last approximately 6 hours in total.
When it passes behind the Moon, the spacecraft will be out of contact with the Earth for 40 minutes - no doubt an eternity for those back in mission control waiting to hear from the crew.
"They have a series of different cameras - they're going to get data from that," NASA administrator Jared Isaacman told CBS News.
"They've actually had an opportunity for three and a half years to train for this mission, to work with our scientists on the information they would like to gather most about the far side of the moon."
As always, NASA will be livestreaming the entire thing - you can check out the feed below.