Technicians are simultaneously manufacturing NASA’s Space Launch System (SLS) core stages for the Artemis II and Artemis III lunar missions at NASA’s Michoud Assembly Facility in New Orleans. The core stage for the deep space rocket consists of two huge propellant tanks, four RS-25 engines, and miles of cabling for the avionics systems and flight computers. All the main core stage structures for Artemis II, the first mission with astronauts, have been built and are being outfitted with electronics, feedlines, propulsion systems, and other components. Engineers are welding the core stage structures for the Artemis III mission, which will land the first woman and the next man on the lunar surface, through a process called friction stir welding. The manufacturing progress for Artemis II and III comes as the first core stage for the SLS rocket undergoes Green Run testing at NASA’s Stennis Space Center in Bay St. Louis, Mississippi.