The Vanguard was designed and built by the Martin Company for the U.S. Naval Research Laboratory. Scout [Illustration: 69. Four-stage Scout vehicle launches satellite from the Western Test Range, California.] [Illustration: 70. Scout in vertical position prior to the launch of an Explorer science satellite, April 29, 1965.] On February 16, 1961, Scout became the first solid-propellant vehicle to orbit a satellite (_Explorer 9_). It is a four-stage launch vehicle that can perform a variety of space and reentry research tasks. Its relatively low cost has made it a popular choice for many satellite programs, including Transit navigation satellites, the Small Astronomy and Small Scientific Satellites, the Beacon Explorer, Hawkeye, Micrometeoroid, Meteoroid Technology, and Solrad satellites. The rocket has also been used extensively to launch foreign satellites. ANS-A (Netherlands), GRP-A (Germany), UK-5 (England), Eole (France), San Marco 5 (Italy), and the ESRO satellites for the European Space Research Organization (now European Space Agency) have all gone aloft aboard Scout launch vehicles. The satellite in the nose of the Scout on exhibit is an INJUN/Air Density Explorer identical to that launched from Wallops Island, Virginia, on August 8, 1968. Scout was built by the LTV Aerospace Corporation for the National Aeronautics and Space Administration and the Department of Defense. The Scout is from the National Aeronautics and Space Administration and LTV Aerospace Corporation. Minuteman III [Illustration: 71. Minuteman III launch from Vandenberg AFB, California.] The Minuteman III is the standard U.S. land-based intercontinental ballistic missile. This three-stage solid-propellant missile is launched from underground silos that are 24.4 meters (80 feet) deep and 3.7 meters (12 feet) in diameter. These missiles can be launched either from underground control centers or by an airborne launch control center installed in KC-135 aircraft. Minuteman III was first test-fired on August 16, 1968, and has since replaced earlier Minuteman series ICBMs in the operational system. This missile was designed by Boeing for the Air Force Strategic Air Command. This missile is from the US. Air Force and Boeing Aerospace Corporation. Poseidon C-3 [Illustration: 72. Launch of Poseidon from nuclear-powered submarine.] This two-stage solid-propellant Fleet Ballistic Missile is launched underwater from nuclear-powered submarines. The Poseidon is launched by compressed air, with first-stage ignition just after the missile is clear of the hull. Poseidon carried the Mk-3 Multiple Independently targeted Reentry Vehicles (MIRV)—thermonuclear weapons which enable a single missile to cover a number of targets.