Viking was series of twelve sounding rockets designed and built by the Glenn L. Martin Company under the direction of the U.S. Naval Research Laboratory (NRL). Designed to supersede the German V-2, the Viking was the most advanced large, liquid-fueled rocket developed in the United States in the late 1940s, returning valuable scientific data from the edge of space between 1949 and 1955. Viking 4, launched in 1950, was the first sounding rocket to be launched from the deck of a ship.