This is the Cajun second stage of the Nike-Cajun sounding rocket. The Nike first stage (not shown here) was a modified solid-fuel booster rocket originally developed by the Army for the Nike-Ajax anti-aircraft missile system. Scientific instruments-ranging in weight from ten to one hundred pounds-carried in the Cajun's nose took measurements of the upper atmosphere. The Cajun, launched from a Nike-Ajax launcher, could reach a maximum altitude of fifty miles. The motor for the Cajun, built by the Thiokol Chemical Corporation, produced 9,620 pounds of thrust for three seconds.
The National Advisory Committee for Aeronautics donated an entire Nike-Cajun sounding rocket to the Smithsonian in 1958.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.