Thats what is fun about this Blog , we can cover so many things that glow or Illumanate light in the dark or light . Check out a Peacock Spider if you get time.Light falls on the top layer first, and some of it is reflected; some light, however, penetrates down to the lower layer, where it is reflected there. Both reflected waves make their way back up to the surface, but by this stage, they’re traveling across different distances and perhaps at different angles.
That means that when they meet up again at the surface, they will either interfere with each other constructively or destructively – "add" or "subtract" – which ultimately produces a range of colors. This process is known as structural coloration, and involves a range of incredibly small structures and materials. Incidentally, the gradual changing of color depending on the angle of viewing is known as iridescence, something you can readily observe in a soap bubble.
The team behind this study, led by the University of California San Diego, wanted to know how these two peacock spiders produced their own characteristic iridescence, something that no other beastie is able to replicate.
It turns out that these spiders are armed with novel scales that coat their abdomens. As well as being curved in highly specific ways, the scales also appear to be adorned with a grate-like pattern, one that diffracts (bends) waves of light.