Orion ESM

An artist’s impression of the Orion crew capsule with ESA’s service module.
The module sits directly below the capsule and provides propulsion, power, thermal control, and water and air for four astronauts. The solar array spans 19 m and provides enough to power two households.
A little over 5 m in diameter and 4 m high, it weighs 13.5 tonnes. The 8.6 tonnes of propellant will power one main engine and 32 smaller thrusters.