These reflective wafers are thermal control mirrors. They are for use on the exterior of communications satellites to help regulate the interior temperature. The interior of a satellite houses the communications payload and a range of supporting technologies (such as batteries) which are designed to operate at room temperature (15-20 C, on average).
Controlling the temperature of a satellite is a complex problem. The cold of space drains heat from the satellite, while the sun's light adds thermal energy to the spacecraft. In addition, the operation of the communications payload and other devices generates heat. All of these effects must be balanced to maintain a "room temperature" environment in the spacecraft interior.
These thermal control mirrors play a part in that balancing process. The reflective surface bounces sun energy away from the satellite. In turn, the glass backing of these mirrors allows heat from the interior of the spacecraft to escape into space.
Lockheed Martin donated this set of mirrors to the Museum in 1998.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Country of Origin
United States of America
Type
SPACECRAFT-Uncrewed-Parts & Structural Components
Manufacturer
Optical Coating Laboratory, Inc.
Dimensions
Each Mirror: 1 21/32" x 1 21/32"
Storage: 11 5/8" x 9 1/2" x 3 3/8"
Materials
Glass
Silver
Styrofoam
Paper
Adhesive
Ink
Inventory Number
A19980297000
Credit Line
Gift of Lockheed Martin
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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