The detection of color is as a result of objects absorbing energy in the visible range and the consequential emission of radiation to the observer. For opaque objects, those that absorb on the red end will reflect or transmit on the blue end of the visible region. When we venture on the other side of the visible region of the spectrum, we come to the ultra-violet region. This relatively short wavelength electromagnetic radiation is associated with a large enough quantity of energy to cause the burning of skin tissue. Ultraviolet radiation can cause damage to the retina of the eyes if the radiation and exposure time is great enough.
Ultraviolet radiation is the most common form of energy for most photochemical reactions.
Ultraviolet radiation is energetic enough to affect the electronic states of molecules. Ultraviolet radiation comes from the expansiveness of space, but thanks to the ozone layer of our atmosphere, this potentially harmful radiation is absorbed and effectively filtered out before much of it reaches the earth's surface. Instruments designed to impact ultraviolet radiation upon molecules allows for the detection of the presence of substances and their identification. The most lethal region of the spectrum is the X-Ray and gamma ray regions. The shortness of the wavelength is associated with energy that can cause death with only a short exposure.