American ICBM-derived heavy-lift orbital rocket

Titan started as an ICBM and ended as an indispensable launch platform. The Titan II flew all twelve Gemini missions, ten of them crewed, in 1964–1966; later variants hauled classified NRO spy satellites and planetary probes until the final Titan IV-B flight in October 2005. Across all variants, Titan flew for 46 years.