Extreme Ultraviolet Explorer
The Extreme Ultraviolet Explorer was a NASA space telescope for ultraviolet astronomy. EUVE was a part of NASA's Explorer spacecraft series. Launched on 7 June 1992. With instruments for ultraviolet (UV) radiation between wavelengths of 7 and 76 nm, the EUVE was the first satellite mission especially for the short-wave ultraviolet range. The satellite compiled an all-sky survey of 801 astronomical targets before being decommissioned on 31 January 2001.
The Extreme Ultraviolet Explorer spacecraft prior to launch
Ultraviolet astronomy is the observation of electromagnetic radiation at ultraviolet wavelengths between approximately 10 and 320 nanometres; shorter wavelengths—higher energy photons—are studied by X-ray astronomy and gamma-ray astronomy. Ultraviolet light is not visible to the human eye. Most of the light at these wavelengths is absorbed by the Earth's atmosphere, so observations at these wavelengths must be performed from the upper atmosphere or from space.
A GALEX image of the spiral galaxy Messier 81 in ultraviolet light. Credit:GALEX/NASA/JPL-Caltech.
Andromeda Galaxy - in high-energy X-ray and ultraviolet light (released 5 January 2016).