Why Are Satellites Wrapped In Gold?
The golden wrapping, with which many satellites and space probes are provided before launch, functions as insulation and ensures that the equipment gets neither too cold nor too warm in space. The satellite must remain above a minimum temperature to allow its electronics to work properly. The golden colour reflects the sunlight, so it does not heat the equipment. The insulation consists of several layers of foil, which also offers slight dust grain collision protection.
The foil used to include gold, but now, it is typically made of the kapton plastic material covered in a thin layer of aluminium. The combination makes the insulation resemble gold, but is much stronger.