Crews transfer the main stage of a United Launch Alliance Atlas V rocket to the Vertical Integration Facility at Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida on Wednesday, Feb. 21, 2024. The rocket will send two NASA astronauts to the International Space Station aboard Boeing’s CST-100 Starliner capsule no earlier than mid-April for NASA’s Boeing Crew Flight Test. The mission will test the end-to-end capabilities of Starliner and its system and, if successful, will pave the way for NASA’s certification ahead of regular missions to the space station as part of the agency’s Commercial Crew Program.