Louvers, Temperature Control System, Mariner 2

The louvers on the Mariner 2 mission to Venus in 1962 provided a key aspect of the spacecraft’s temperature control system. Surrounded by a magnesium frame, the eight aluminum slats would automatically open when Mariner’s temperature began to rise, releasing excess heat, and close when the temperature dropped, holding in available warmth. The louvers offered a final fail-safe should the satellite’s thermal control units (various paints and platings to absorb or dispel heat) fail to fully moderate Mariner 2’s temperature. During flight, a number of solar panels malfunctioned, causing Mariner’s temperature to fluctuate. Despite the variety of thermo-control units, temperatures reached 75°F higher than anticipated. However, the scientific experiments studying the planet Venus were not affected.

NASA's Jet Propulsion Laboratory transferred these louvers to the Museum in 1976.