High purity gold reflects heat energy almost completely. That makes it ideal for heat and radiation reflection. Gold-coated visors protected astronauts' eyes from searing sunlight on the Apollo 11 moon landing.
Gold not only will reflect heat, but it also is an excellent conductor of heat. It is used in many electronic processes to draw heat away from delicate instruments. The main engine nozzle of the space shuttle uses a 35% gold alloy, for example.
Learning more about the unique properties of gold has helped me appreciate my American gold coins and world gold coins much more. As easily as gold can be damaged, I'm surprised so many rare gold coins have survived as well as they have. https://www.a1mint.com/shop/