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The Artemis I mega lunar rocket is ready to refuel.
The fourth attempt at a final pre-launch test began on Saturday, with refueling of the rocket due to begin Monday morning.
The crucial test, known as the wet dress rehearsal, simulates every stage of the launch without the rocket leaving the launch pad at Kennedy Space Center in Florida.
This process includes loading supercold propellant, performing a full launch-simulating countdown, resetting the countdown clock, and draining the rocket’s fuel tanks.
The results of the dress rehearsal will determine when the uncrewed Artemis I embarks on a mission that will go beyond the moon and back to Earth. This mission will launch NASA’s Artemis program, which is expected to return humans to the Moon and land the first woman and first person of color on the lunar surface by 2025.
Three previous attempts at a wet dress rehearsal in April failed, ending before the rocket could be fully loaded with propellant due to various leaks. These have since been corrected, according to NASA.
The NASA team brought the 322-foot-tall (98-meter-tall) Artemis I rocket stack, including the Space Launch System and Orion spacecraft, back to the launch pad at Kennedy Space Center in Florida June 6.
The wet dress rehearsal began at 5 p.m. ET on Saturday with a “station call” – when all teams associated with the mission arrive at their consoles and signal that they are ready for the test to begin and launch an account two days countdown. .
Preparations for the weekend will set up the Artemis team to begin loading propellant into the rocket’s core and upper stages.
There is currently a live view of the rocket on NASA’s website, with intermittent commentary.
The mission management team chairman has given the go-ahead to begin refueling, but the team is waiting for the launch director to officially decide when to begin.
Tanking is currently suspended due to an identified issue with the backup nitrogen gas supply. The launch team has already replaced the valve causing the problem. The wait can last up to 90 minutes.
A two-hour test window will begin later Monday, with the Artemis team targeting the first countdown at 2:40 p.m. ET.
First, the team members will go through a countdown up to 33 seconds before launch, then stop the cycle. The clock will be reset; then the countdown will resume and run until approximately 10 seconds before a launch occurs.
“During the test, the team may hold out during the countdown if necessary to verify conditions before resuming the countdown, or extend beyond the test window, if necessary and resources permitting. “, according to an update on NASA’s website.
Previous wetsuit rehearsal attempts have already achieved many goals in preparing the rocket for launch, Charlie Blackwell-Thompson, Artemis launch director for NASA’s Exploration Ground Systems program, told a conference at press on Wednesday.
“We hope to complete them this time around and get through the cryogenic loading operations as well as the terminal count,” she said. “Our team is ready to go, and we can’t wait to get back to this test.”
The mission team is studying possible launch windows to send Artemis I on its journey to the moon in late summer: August 23 to August 29, September 2 to September 6, and beyond.
After the Artemis rocket stack completes its dress rehearsal, it will return to the Space Center’s Vehicle Assembly Building to await launch day.
There’s a long history behind the arduous testing of new systems before a launch, and the Artemis team faces experiences similar to those of the Apollo and shuttle-era teams, including multiple test attempts and delays.
“There is not a single person on the team who shirks the responsibility that we have to manage ourselves and our contractors and to deliver, and delivering means meeting those flight test goals for ( Artemis I), and achieve the goals of the Artemis I,” said Jim Free, associate administrator for NASA’s Exploration Systems Development Missions Directorate, during last week’s press conference.