The name is a compound of the acronym VANTA (vertically aligned nanotube arrays) and the color black. The material known as Vantablack is one of the darkest substances known, absorbing up to 99.965% of visible light (at 663 nm if the light is perpendicular to the material) is a material developed by Surrey NanoSystems in the United Kingdom. One scientific measure of darkness is the Bortle Dark-Sky Scale, which indicates the night sky's and stars' brightness at a particular location, and the observability of celestial objects at that location. Also, the light detecting cells in the human eye ( rods and cones) will regenerate more unbleached rhodopsin when adapting to darkness. When a vertebrate, like a human, enters a dark area, its pupils dilate, allowing more light to enter the eye and improving night vision. Exposure to alternating light and darkness (night and day) has caused several evolutionary adaptations to darkness. An object may appear dark, but it may be bright at a frequency that humans cannot perceive.Ī dark area has limited light sources, making things hard to see. For example, matte black paint does not reflect much visible light and appears dark, whereas white paint reflects much light and appears bright. In terms of physics, an object is said to be dark when it absorbs photons, causing it to appear dim compared to other objects. In perceiving, the eye is active, and the part of the retina that is unstimulated produces a complementary afterimage. The perception of darkness differs from the mere absence of light due to the effects of after images on perception.