The first mission of the American programme return to the moon, Artemis 1 is an unmanned mission around the moon.
Block 1, the basic version of the Space Launch System, is Nasa's heavy launcher.
At its top, the Orion spacecraft. After releasing the boosters, the core stage separates from the spacecraft. Orion goes into orbit around the Earth. It is the intermediate cryogenic propulsion stage (ICPS) that will give Orion the big thrust needed to leave the Earth's orbit and head for the Moon.
To navigate in space, Orion will be powered by a service module that also generates air and water for astronauts on future missions. Orion will approach to around 100 km from the Moon, and will take advantage of its gravitational force to reach a distant orbit at about 70,000 km from the Moon during between 6 and 19 days.
Once Orion's performance has been analysed, the module will head back to Earth, taking advantage of the Moon's gravitational pull. One of the challenges of Artemis 1 is to successfully re-enter the Earth's atmosphere at very high speed, to test the performance of its heat shield and to successfully complete the landing in the Pacific.
Also watch: Your quick guide to Artemis 1, NASA's new mission to the Moon
Nasa will conduct scientific experiments in deep space with several Cubesat or nanosatellites deployed during the mission.
If the results of this mission, which should last from 4 to 6 weeks, are validated, it will be followed by the Artemis 2 mission, which will carry 4 astronauts around the Moon on board the Orion spacecraft.