Newly discovered carbon may yield clues to ancient Mars

NASA's Curiosity rover landed on Mars on Aug. 6, 2012, and since then has roamed Gale Crater taking samples and sending the results back home for researchers to interpret. Analysis of carbon isotopes in sediment samples taken ...

Generating glow-in-the-dark light using organic materials

Glow-in-the-dark materials are used worldwide for emergency signs, watches, and paint. This useful characteristic fuels a global market worth approximately US$400 million. But the inorganic crystals that are currently needed ...

Image: Hubble surveys a snowman sculpted from gas and dust

The Snowman Nebula is an emission nebula that resides in the constellation Puppis in the southern sky, about 6,000 light-years away from Earth. Emission nebulae are diffuse clouds of gas that have become so charged by the ...

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Ultraviolet

Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than x-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV. It is so named because the spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the color violet.

UV light is found in sunlight and is emitted by electric arcs and specialized lights such as black lights. As an ionizing radiation it can cause chemical reactions, and causes many substances to glow or fluoresce. Most people are aware of the effects of UV through the painful condition of sunburn, but the UV spectrum has many other effects, both beneficial and damaging, on human health.

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