European Service Module

The European Service Module is the service module of the Orion spacecraft, providing its primary power and propulsion until it is discarded at the end of each mission. NASA announced in January 2013 that the European Space Agency would contribute the module for Artemis I, based on the agency Automated Transfer Vehicle, and Airbus Defence and Space delivered the first one from Bremen, Germany, at the end of 2018. It is about 5.0 metres in diameter and 4.0 metres long and made of aluminium-lithium alloy, and for the first six modules the main engine is a refurbished AJ10-190 supplied by NASA that had flown on the Space Shuttle. It provides the water and oxygen for a habitable environment, generates and stores electrical power, and can support a crew of four for 21 days. The module first flew on Artemis I on 16 November 2022, and ESA plans to provide modules up to Artemis VI. On the 2026 Artemis II mission a helium leak was seen in its pressurization system, and NASA said the valve system will probably need design changes.