The mission will include the fourth use of a Space Launch System (SLS) launch vehicle, will send an Orion spacecraft with four astronauts to the Lunar Gateway space station, install a new module on the Gateway, and conduct the second lunar landing of the Artemis program.
[2] The mission will deliver and install the International Habitation Module (I-Hab) of the Lunar Gateway space station.
[6] Gateway is a small modular space station to be established in Near-rectilinear halo orbit (NRHO) in late 2024.
[9] The heavier total mass of the SLS Block 1B vehicle requires use of the Mobile Launcher-2 ground support equipment.
The NASA Office of Inspectior General (OIG) estimates the earliest that ML-2 will be available for Artemis IV is November 2026.