NASA to push ahead with ‘wet’ dress rehearsal for Artemis II moon mission
January 27, 2026
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NASA continues its “wet” dress rehearsal for Artemis II lunar mission
A crucial test of NASA’s next crewed flight to the Moon is expected to take place as early as Saturday, the agency said.
from NASA Artemis II The Space Launch System (SLS) rocket and Orion spacecraft are illuminated by lights at Launch Complex 39B on January 17, 2026, at NASA’s Kennedy Space Center in Florida.
NASA prepares for launch Artemis II, the agency’s highly anticipated first crewed mission to the Moon in more than half a century. A crucial step is Artemis IIThe “wet” dress rehearsal for , a major test of the Space Launch System (SLS) rocket and the Orion capsule that will house the mission’s four astronauts. At Florida’s Kennedy Space Center, engineers will attempt to fuel the rocket and simulate a countdown to its launch as early as Jan. 31, the agency said in an update Monday.
If all goes well, the agency’s plan to launch four astronauts around the Moon and back to Earth will continue, with a launch date as early as the first week of February.
The dress rehearsal will see NASA technicians load the uncrewed spacecraft rocket with more than 700,000 gallons of cryogenic fuel, specifically liquid oxygen and liquid hydrogen, before beginning a countdown to launch.
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The test could, however, result in the SLS and Orion being removed from the launch pad for additional DIY work. That’s what happened in 2022, when the uncrewed Artemis I mission caused multiple liquid hydrogen leaks on the launch pad and during testing – a recurring problem that significantly delayed its launch.
Apart Artemis IIAs the wet dress rehearsal approaches, NASA is also testing the water systems aboard Orion to ensure its water is safe to drink. “Early samples showed higher levels of total organic carbon than expected,” the agency said in the same update Monday. Authorities also made adjustments to the parking area’s emergency exit system. The system is made up of a series of gondola-shaped baskets intended to transport the crew and launch pad personnel to safety, in the event of a problem.
Weather conditions could also affect the timing of Artemis IIthe launch. Temperatures at the Space Center reached 40 degrees Fahrenheit on Tuesday, but are expected to rise through the weekend. The agency is taking steps to prepare for colder-than-usual temperatures, NASA said in the same statement.
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