Minotaur IV

Minotaur IV, also known as Peacekeeper SLV and OSP-2 PK is an active expendable launch system derived from the LGM-118 Peacekeeper ICBM. It uses the first three stages of the Peacekeeper missile, combined with a new upper stage. On the baseline version, the fourth stage is an Orion 38. However, a higher performance variant, designated Minotaur IV+, uses a Star-48V instead.