Learn why the James Webb Space Telescope uses gold-coated mirrors, in this video from NOVA: Treasures of the Earth: Metals. Gold is an almost perfect reflector of infrared light. The two ounces of gold covering the mirrors of the telescope will allow it to better study the universe in infrared light. A demonstration with a thermal infrared camera shows the difference in reflectivity between an ordinary silver-coated mirror and a gold-coated mirror.
This resource was developed through WGBH’s Bringing the Universe to America’s Classrooms project, in collaboration with NASA. Click here for the full collection of resources.
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