Space Launch System

The Space Launch System (SLS) is an American Space Shuttle-derived super heavy-lift expendable launch vehicle, which has been under development by NASA in the United States since its announcement in 2011. It has become the primary launch vehicle of NASA's deep space exploration plans including the planned crewed lunar flights of the Artemis program to the Moon and a possible follow-on human mission to Mars. The first 3 flights will use the Block 1 configuration with a modified Delta Cryogenic Second Stage (DCSS) from the Delta IV family called the Interim Cryogenic Propulsion Stage (ICPS). It was planned to debut a larger, more powerful Block 1B configuration with an Exploration Upper Stage (EUS) on the fourth flight, but this configuration was cancelled in favor of a "standardized" near-Block 1 configuration with a Centaur V upper stage from ULA's Vulcan rocket.