What makes the colors in the rainbow?
A rainbow is made up of seven colors: red, orange, yellow, green, blue, indigo, and violet. These however are just the colors that we can see. The spectrum of light includes a much broader range of wavelengths, including infrared, ultraviolet, x-ray, and even radio waves, the rainbow is just a small part of the light spectrum, we call it the visible light spectrum.
When you see a rainbow in the sky you are looking at light waves refracting in water vapor. Water acts as a prism and separates the various wavelengths of light, making them visible individually.
Quite a site, too bad we can’t see even more of the light spectrum.