NASA began a two-day practice countdown Saturday leading up to the fueling of its new moon rocket, a crucial test that will determine when four astronauts blast off on a lunar flyby.

NASA fueled its new moon rocket in one final make-or-break test Monday, with hopes of sending astronauts on a lunar fly-around as soon as this coming weekend. The launch team began loading the 322-foot (98-meter) rocket with super-cold hydrogen and oxygen at Kennedy Space Center late at midday.

NASA is planning to conduct a critical fueling test known as a wet dress rehearsal that will determine if Artemis 2 is on track to launch in Florida.

The countdown for NASA’s next trip around the Moon has shifted from planning to practice, as controllers begin a high‑stakes fueling rehearsal for the Artemis 2 Space Launch System. The wet dress test is designed to push the rocket and ground systems through a full launch‑day script,

NASA's Artemis II mission reached a critical milestone this week as teams conducted a wet dress rehearsal of the Space Launch System rocket and Orion spacecraft during an unusually intense blast of cold air surged across Florida, delivering record-breaking low temperatures to the Sunshine State.

If the countdown and fueling test go well, four astronauts will set their sights on a Super Bowl Sunday launch to the moon.

NASA's crucial pre-launch fueling test for its new moon rocket was interrupted by a hydrogen leak, forcing engineers to pause operations and attempt quick fixes. The outcome will decide whether the Artemis crew can begin their lunar fly-around mission this month.

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If the fueling test goes well, the Artemis II flight around the moon and back could take off as early as Feb. 8.