Ultraviolet Light

light · invisible · sun · energy

Invisible sunlight. Ultraviolet (UV) light comes from the Sun but we cannot see it because the waves are too short. It makes up about 10% of all the energy the Sun sends to Earth.

Shorter wavelengths. UV light has wavelengths between 100 and 400 nanometers, which is shorter than the colored light our eyes can see but longer than the super-powerful X-rays doctors use.

Human-made UV. We can create UV light without the Sun using electric arcs, special mercury lamps, tanning beds, and black lights that make certain things glow in the dark.

Extreme ultraviolet. The shortest UV waves, called extreme ultraviolet, are only 10 to 100 nanometers long and act a lot like soft X-rays, which are even more powerful.