The color black is actually the absence of light. By definition, black is a surface or object that does not reflect any light falling on it. However, there is no paint that fits this definition. Or rather, there wasn’t until the production of Vantablack at the National Physical Laboratory (UK) in 2009. For the sake of scientific accuracy, let’s quickly add that even Vantablack is not truly black, reflecting only 0.035% of the light that falls on it. This alone is enough to make it a magical substance.
But for now, let’s leave aside what Vantablack is, how it was developed, how it works, what it does, and focus on the question “what is black?”. The easier it is to define black, the harder it is to find a black object. By definition, we can say that black is “a surface or object that absorbs all the light falling on it”. But such an object cannot exist. The reason is simple. When a black body absorbs light falling on it, it heats up and radiates this heat to its surroundings.
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What is truly black?
But aren’t black holes truly black objects? Black holes absorb 100% of all radiation (energy) that falls on them. On the other hand, black holes are not “black”, that is, they radiate. This radiation even has a name: Hawking Radiation… Therefore, we cannot consider them as real black bodies (since they do radiate a little). Is the vacuum of space really black? The answer to this question is “no!” But why? Since the vacuum of space contains nothing, shouldn’t it be considered black? But we know that even the most empty regions of space are not empty at all, but filled with a weak light called microwave background radiation.
We can happily call a substance that is black in everyday life, which only absorbs all visible light, “black”. With materials called Vantablack and Super Black, a very high blackness ratio has been achieved. Vantablack actually looks like velvet up close. It is obtained by growing nano-sized carbon tubes vertically on a surface. This forest of carbon tubes traps the light falling on it, preventing it from escaping until it is absorbed. Think of it as side-by-side tubes placed vertically on a surface. Light rays falling on the surface are reflected until they are absorbed inside the tubes. The name VANTA is derived from its working principle: Vertically Aligned Carbon Nanotube Arrays. In other words: Vertically Aligned Carbon Nanotube Arrays.
Among the black paints (including matte paints and super black) Vantablack stands out by far. Compared to it, the other black paints look like gray. Even when illuminated with a very strong light, they don’t lose much of their blackness. Generally, when the viewing angle of a black object approaches 180 degrees, its reflectivity increases. Therefore, when held sideways, all objects begin to shine like mirrors. This is a well-known phenomenon. Even ultraviolet telescopes are made according to this principle. The mirrors used in such telescopes are deep parabolas. However, surfaces coated with Vantablack do not lose their absorbing properties even when viewed from a narrow angle, rendering them invisible. Seeing an object coated with Vantablack gives you a kind of illusion. You feel that something is actually there, but you can’t see it. All you can see is the contour of the object.