Themes > Science > Astronomy > Equipment and Devices > Telescope > Kinds of Telescope > Ultraviolet Telescopes

Some of the hottest and most energetic stars in the universe are visible in the ultraviolet region of the spectrum. However, this light is largely blocked by the earth's atmosphere, and so can only be studied from space. In the 1980s and 1990s a series of highly successful earth-orbiting observatories explored the ultraviolet universe, most notably the International Ultraviolet Explorer (IUE), the Extreme Ultraviolet Explorer (EUVE), the ASTRO space shuttle observatory, and the Hubble Space Telescope (HST). Ultraviolet telescopes are similar to optical reflecting telescopes, but their mirrors have special coatings that reflect ultraviolet light very well. Ultraviolet telescopes provide much information about interstellar gas, young stars, and the gaseous areas of active galaxies.