Spotting merging galaxies

Over 30 years ago, the Infrared Astronomy Satellite discovered that the universe contained many extremely luminous galaxies, some more than a thousand times brighter than our own Milky Way, but which are practically invisible ...

Image: Hubble's portrait of star's gaseous glow

Although it looks more like an entity seen through a microscope than a telescope, this rounded object, named NGC 2022, is certainly not algae or tiny, blobby jellyfish. Instead, it is a vast orb of gas in space, cast off ...

Study gives insight into sun-induced DNA damage and cell repair

A team led by a Baylor University researcher has published a breakthrough article that provides a better understanding of the dynamic process by which sunlight-induced DNA damage is recognized by the molecular repair machinery ...

Hubble captures cosmic fireworks in ultraviolet

Hubble offers a special view of the double star system Eta Carinae's expanding gases glowing in red, white, and blue. This is the highest resolution image of Eta Carinae taken by the NASA/ESA Hubble Space Telescope.

Space station mold survives high doses of ionizing radiation

The International Space Station, like all human habitats in space, has a nagging mold problem. Astronauts on the ISS spend hours every week cleaning the inside of the station's walls to prevent mold from becoming a health ...

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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.

This text uses material from Wikipedia, licensed under CC BY-SA