European Service Module

European Service Module

ESM logo showing the Orion spacecraft exploring the Solar System, with the rear view highlighting the service module
Manufacturer	European Space Agency
Used on	Orion
General characteristics
Height	4 m (13 ft) [1]
Diameter	4.1 m (13 ft) (excluding solar panels)
Gross mass	13,500 kg (29,800 lb) [2]
Propellant mass	8,600 kg (19,000 lb) [2][3]
Derived from	Automated Transfer Vehicle
Launch history
Status	Operational
First flight	November 16, 2022
Propulsion
Powered by	1 × AJ10
Maximum thrust	26.6 kN (6,000 lbf)
Propellant	MON3/MMH

The European Service Module (ESM) is the service module component of the Orion spacecraft, serving as its primary power and propulsion component until it is discarded at the end of each mission. In January 2013, NASA announced that the European Space Agency (ESA) will contribute the service module for Artemis I, based on the ESA's Automated Transfer Vehicle (ATV). It was delivered by Airbus Defence and Space in Bremen, in northern Germany to NASA at the end of 2018. After approval of the first module, the ESA will provide the ESMs from Artemis II to Artemis VI.

The module's first flight was Artemis I, the first major milestone in NASA's Artemis program to return humans to the Moon, on November 16, 2022. The Space Launch System launched Orion toward the Moon, where the ESM placed the spacecraft into distant retrograde orbit around the Moon, and subsequently extracted it from that orbit and sent it back to Earth.

The service module (SM) supports the crew module (CM) from launch through to separation prior to reentry. It provides in-space propulsion capability for orbital transfer, attitude control, and high altitude ascent aborts. It provides the water and oxygen needed for a habitable environment, generates and stores electrical power, and maintains the temperature of the vehicle's systems and components. This module can also transport unpressurized cargo and scientific payloads.^[4]