NASA readies for ‘wet dress rehearsal’ ahead of Artemis II moon launch
As NASA makes final preparations to send four astronauts on a trip around the Moon, a critical test Monday will reveal whether its massive moon rocket is truly ready to fly.
Known as a “wet dress rehearsal,” the test is essentially an elaborate walkthrough on launch day. NASA will fully fuel its next-generation Space Launch System rocket, going through each stage as it would on the day until about 30 seconds before liftoff.
The results will allow engineers and mission managers to assess the booster’s performance and readiness.
The highly anticipated Artemis II mission is expected to launch no earlier than Sunday and send four astronauts on a 10-day journey around the Moon. The path will take the crew further from Earth than any humans have ever gone before.
But the official launch date strongly depends on the outcome of the wet dress rehearsal.
“We’ll take some time after we get wet, we’ll look at the data, and then we’ll prepare for our launch attempt,” Charlie Blackwell-Thompson, Artemis’ launch director, said during a press briefing last month.
If all goes well, NASA could announce a targeted liftoff in the coming days. However, if problems arise, the space agency could be forced to delay the mission.
Engineers and mission managers will countdown to a simulated launch time of 9 p.m. ET on Monday. In the preceding hours, more than 700,000 gallons of cryogenic propellant will be loaded into the rocket. NASA plans to broadcast this tanking process once it begins. In the meantime, the agency is live streaming 24/7 of the Artemis rocket on the launch pad.
As part of the training, mission leaders will set and restart the countdown several times during the last 10 minutes. These stops and starts help engineers assess the health of the rocket, including automatic systems designed to start and take control of the booster about 30 seconds before liftoff.
Artemis II will be the second trip to space for NASA’s Space Launch System rocket and Orion capsule. But it will be the first time they will carry humans, making this mission a crucial step toward achieving NASA’s goal of returning astronauts to the lunar surface.
The Artemis II crew – NASA astronauts Reid Wiseman, Christina Koch and Victor Glover and Canadian astronaut Jeremy Hansen – have spent the last week and a half in quarantine at NASA’s Johnson Space Center in Houston to stay healthy ahead of the mission.
NASA launched the Space Launch System rocket, topped with the Orion capsule, to the launch pad at the Kennedy Space Center in Florida on January 17. The agency had originally planned to conduct the wet dress rehearsal on Saturday, but pushed back the schedule to wait out unusually frigid weather. A weekend cold snap sent temperatures plummeting across the Southeast and Mid-Atlantic.
As such, NASA has ruled out the first two launch opportunities (Friday and Saturday) in this month’s window, which runs through February 11. The space agency said there are possible launch windows in March and April, if necessary.
To keep the launch on track this month, the wet dress rehearsal will likely need to go off without a hitch.
If the test reveals problems requiring additional work, NASA may have to return the rocket to its Vehicle Assembly Building. The uncrewed Artemis I flight around the Moon in 2022 has been delayed by six months due to hydrogen leaks identified during its first wet dress rehearsal.
