Explorer 39 was an inflatable sphere, 3.6 m in diameter. It was orbited to make atmospheric density determinations.

The Scout family of rockets were were American launch vehicles designed to place small satellites into orbit around the Earth. The Scout multistage rocket was the first orbital launch vehicle to be entirely composed of solid fuel stages.

The National Aeronautics and Space Administration is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research. NASA have many launch facilities but most are inactive. The most commonly used pad will be LC-39B at Kennedy Space Center in Florida.