The Douglas Thor, called "the DC-3 of the Space Age," was the first intermediate-range ballistic missile (IRBM) deployed since the German V-2. Thor was used as the first-stage rocket to launch NASA's first (America's fifth) satellite into space Oct. 11, 1958, and continued to be used as a launch vehicle until 1981. Thor missiles provided first the hardware, then the technology, for current Air Force and NASA launch systems, including Delta and Delta II launch vehicles.