This week, NASA announced that they managed to produce real black black paint. The image shows the structure of the nano paint under a microscope.
What is black? There was an interesting discussion on Quora, the other day, about black. Go check it out, some interesting things came up. My own definition of black, as written on Quora, is:
"No light. The perfect black surface reflects or emits no light at all."
Which implies that black paint absorbs all light. However, the blackest of black paints only absorbs some 90% of light max. So black paint isn't actually black. It's dark grey. And then there's the invisable light: infrared and ultraviolet. They're more important than you think, because they contribute much to the heat buildup in a paint surface. It is always said that a dark surface becomes warmer than a light surface. While this may be true in most cases, it disregards the effect of UV and infrared. Some dark surfaces won't get as warm as you'd expect because they won't absorb UV and infrared.
So now Nasa came up with a black paint that absorbs up to 99.5% of all light, including infrared and UV. If you would use that paint on your house, it would become a bit of a black hole. I wouldn't recommend it. But I'd love to see it nonetheless.