For the moon of Saturn, see Mimas (moon).The Saturn I (pronounced "Saturn one") was the United States' first heavy-lift dedicated space launcher, a rocket designed specifically to launch large payloads into low Earth orbit. Most of the rocket's power came from a clustered lower stage consisting of tanks taken from older rocket designs strapped together to make a single large booster, leading critics to jokingly refer to it as "Cluster's Last Stand".