All Ranger spacecraft utilized the Sun to power their scientific payloads. Solar panels supplemented on-board-batteries to provide electrical power which allowed the spacecraft to function. Ranger VIII was no exception and it utilized four aluminum actuators to deploy its solar panels. Weighing 1.15 lb (each), the springs could release a load between 30 and 160 lbs. The actuators consist of two concentric cylinders which load the stainless steel spring as well as two steel pistons. To moderate the spring's force distribution, the actuators were filled with silicone oil. Ranger 8’s solar panels functioned perfectly on its flight.
NASA's Jet Propulsion Laboratory transferred this object to the Smithsonian Institution in 1969.
Gift of William A. Saley