NASA’s Guide To The Steps Taken During The 48-Hour Countdown For Artemis 1

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NASA has provided a step-by-step guide to the 48-hour countdown of the launch of the Artemis 1 mission to the Moon. The last time NASA launched a rocket to the Moon was in 1972. Back then, NASA used the legendary Saturn V rocket to launch the Apollo missions and land U.S. astronauts on the Moon. As part of its return, NASA built the massive 212-feet-high SLS rocket, the world’s tallest and most powerful rocket.

It has taken NASA 50 years to finally find its way back to the Moon and the Artemis 1 mission, the first of a series of missions, is set to launch this June. The goal of the mission is to test the new SLS (Space Launch System) rocket. The mission will also test the Orion spacecraft which will orbit around the Moon and return to Earth, uncrewed.

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NASA revealed the steps for the two-day countdown of the Artemis 1 launch. During a wet dress rehearsal for the launch, the team at Kennedy Space Center takes on all the steps that are taken during a real launch except for igniting the booster. Countdowns include milestones for “L Minus” (time to liftoff in hours) and “T Minus” (sequence of events built into the launch countdown). The complex launch countdown also includes “holds” to target a precise launch window, or to accommodate tasks without impacting the schedule of the Artemis mission.

The countdown begins once the NASA team arrives and takes their stations. The first milestone is at 45 hours to launch when the water tank for the sound suppression system is filled. The water system prevents any damage to the spacecraft due to violent sound oscillations. At minus 40 hours to launch, the Orion spacecraft will be powered up, and the RS-25