Hubble Space Telescope (HST) at Lockheed Facility during preflight assembly

A mechanical arm positions the axial scientific instrument (SI) module (orbital replacement unit (ORU)) just outside the open doors of the Hubble Space Telescope (HST) Support System Module (SSM) as clean-suited technicians oversee the process. HST assembly is being completed at the Lockheed Facility in Sunnyvale, California.