As NASA prepares too return humans to the vicinity of the Moon, a critical test of the Artemis 2 mission has been slightly delayed. The Space launch System rocket’s full-scale propellant loading, a key component of the Wet Dress Rehearsal, is now scheduled to begin January 31, pushing the potential launch window to no earlier than February 6 [[1]]. This unmanned flight will send the Orion spacecraft and a crew of four astronauts on a lunar flyby – the first crewed mission to the Moon in more than 50 years – and is a crucial steppingstone towards future lunar landings and eventual missions to Mars [[3]].
NASA has adjusted the schedule for a critical test of the Artemis 2 mission, moving the start of the full-scale propellant loading of the Space Launch System (SLS) rocket from January 29 to January 31. This is a pivotal step before the planned launch that will send astronauts around the Moon for the first time in over half a century.
The test, known as the Wet Dress Rehearsal, is targeted for completion by February 2, according to NASA. If all goes according to plan, the Artemis 2 mission could lift off as early as February 6. The test will simulate the entire fueling process, countdown procedures, and final moments before launch, utilizing cryogenic fuels.
The SLS rocket and Orion spacecraft were moved from the Vehicle Assembly Building at Kennedy Space Center to Launch Complex 39B on January 17. Since then, the team has connected the mobile launcher to ground support structures and begun preparing the rocket for the final series of tests.
The Wet Dress Rehearsal will officially begin approximately two days before the simulated launch time. The most significant activity will take place on Saturday, when teams will begin loading over 700,000 gallons (approximately 2.65 million liters) of cryogenic propellant into the rocket’s two main stages, bringing the total weight to around 5.75 million pounds (approximately 2.6 million kilograms) when fully fueled.
The goal of the test is to run the mission clock down to 33 seconds before a simulated launch, the point at which the rocket’s computers take over for final checks. The clock will then be reset to 10 minutes and the countdown resumed, testing the procedures for stopping, restarting, and recovering the mission clock in various scenarios. This meticulous process is crucial for ensuring the reliability of the complex launch sequence.
NASA acknowledges that potential risks remain that could delay the launch. The agency is drawing lessons from the Artemis 1 mission, which required four Wet Dress Rehearsals and encountered fuel leaks that necessitated three returns to the Vehicle Assembly Building. Officials have confirmed that those issues have been addressed.
Weather conditions also pose a challenge. Temperatures at Kennedy Space Center are forecast to drop below freezing this weekend, an unusual occurrence for the area. NASA is taking measures to ensure the environmental control systems for both the Orion spacecraft and the SLS rocket can maintain appropriate conditions. This caution stems from the lessons learned from the 1986 Space Shuttle Challenger disaster.
The Artemis 2 crew is currently in health quarantine ahead of the mission. The team includes Reid Wiseman, mission commander; Victor Glover, pilot; Christina Koch, mission specialist; and Jeremy Hansen, a Canadian Space Agency astronaut.
The approximately 10-day Artemis 2 mission will see the SLS rocket send the Orion spacecraft and crew into Earth orbit before traveling to lunar orbit along a free-return trajectory. This will allow for testing of the spacecraft’s systems and verification of its safety for future landing missions.
While Artemis 2 won’t land on the lunar surface, it represents a significant step in human space exploration and serves as a bridge to Artemis 3, currently planned for 2028. NASA also has plans to expand the Artemis program infrastructure, including the Gateway space station and a new generation of human landing systems.
