The Little Joe 1 was a solid fuel booster rocket that was designed to test the Mercury spacecraft Launch Escape and Recovery systems. The Little Joe program was developed to minimize the cost per launch for the numerous early test flights when compared to similar launch systems as the Atlas and the Redstone rockets. The name "Little Joe" comes from the game of craps, because a cross-section of the designers' blueprints of the four engines looked like four dots, or a double-deuce throw of dice, or in craps parlance, "Little Joe from Kokomo".Photo credit: NASA