Workers use a crane to lift the left-hand forward segment up for transfer into High Bay 3 of the Vehicle Assembly Building for NASA’s Space Launch System (SLS) in the transfer aisle of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Feb. 18, 2021. The forward segment will be attached to the center forward segment on the mobile launcher. Workers with Exploration Ground Systems and contractor Jacobs teams are stacking the twin five-segment boosters on the ML over a number of weeks. When the core stage arrives, it will join the boosters on the mobile launcher, followed by the interim cryogenic propulsion stage and Orion spacecraft. Manufactured by Northrop Grumman in Utah, the twin boosters provide more than 75 percent of the total SLS thrust at launch. The SLS is managed by Marshall Space Flight Center in Huntsville, Alabama. Under the Artemis program, NASA will land the first woman and the next man on the Moon by 2024. The first in a series of increasingly complex missions, Artemis I will test the Orion spacecraft and SLS as an integrated system ahead of crewed flights to the Moon.