This is the U.S. Navy Sparrow 2 air-to-air missile, designed and built by the Douglas Aircraft Company. It was a highly maneuverable missile designed for U.S. Navy aircraft and was similar to the Sparrow 1, America's first operational air-to-air guided missile, but the Sparrow 2 had a more advanced guidance system.
The Sparrow family of missiles originated in 1946 and became one of the largest and most important missile programs for the United States, NATO, and other U.S. allies. A branch of the Sparrow family exists today as the AIM series of missiles.
This missile was donated to the Smithsonian in 1959 by the U.S. Naval Missile Center.
This object is on display in Korea and Vietnam Aviation at the Steven F. Udvar-Hazy Center in Chantilly, VA.