Sorry, I was thinking of teeth. That's this thing. I kept hearing this fan noise, and looking around for it, but it's right here. There's a fan in here. Yes we do.
Gold is also a good reflector.
We use gold with thermal control. One of the biggest problems with spacecraft is that they get too hot or too cold. And if you've ever seen pictures of spacecraft, you'll notice that they always have these shiny gold blankets on them. Those are called thermal blankets. And when their reflective surface is gold they have a low emmisivity, which means it doesn't emit much IR radiation.