|Credit: Hercules Aerospace Products Group, Duncan|
In this historical photo from the U.S. space agency, a Pegasus launch vehicle lays on the ground before its flight on a B-52 in Sept. 1989.
An air-launched, three stage, all solid- propellant, three-axis stabilized vehicle, the Pegasus can set a 400-1,000 pound payload into low-Earth orbit. For more information about Pegasus, please see Chapter 5 in Roger Launius and Dennis Jenkins' book To Reach the High Frontier published by The University Press of Kentucky in 2002.
Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).