This article is about the telescope on the Canary Islands. For the future ESA space telescope, see Herschel Space Observatory.

The William Herschel Telescope or WHT was first conceived in the late 1960s, when the Anglo-Australian Observatory was being designed. The British astronomical community saw the need for telescopes of comparable power in the Northern Hemisphere. Planning began in 1974, but by 1979 the project was on the verge of being scrapped due to a ballooning budget. A re-design cut the price-tage substantially, and Dutch astronomers took a 20% stake in the project, allowing the project to be given the go-ahead in 1981. That year was the 200th anniverary of the discovery of Uranus by William Herschel, and it was decided to name the telescope in his honour. The telescope is a member of the Isaac Newton Group of Telescopes. The Isaac Newton Group of Telescopes or ING operates the WHT, INT and JKT for PPARC, the NWO and the IAC. The Group is located on La Palma in the Canary Islands. ... The seeing statistics for Roque de los Muchachos Observatory make it the third best location for optical and infrared astronomy after Dome C, Antarctica and Mauna Kea Observatory, Hawaii. ... This article discusses one of the Canary Islands. ... Capitals Las Palmas de Gran Canaria Santa Cruz de Tenerife Area  â€“ Total  â€“ % of Spain Ranked 13th  7 447 km²  1,5% Population  â€“ Total (2003)  â€“ % of Spain  â€“ Density Ranked 8th  1 843 755  4,4%  247,58/km² Demonym  â€“ English  â€“ Spanish  Canary Islander (Canarian)  canario/a Statute of Autonomy August 16... Cassegrain may refer to the Cassegrain Reflector Laurent Cassegrain, catholic priest and teacher and probably the inventor of the Cassegrain Reflector Sieur Guillaume Cassegrain, French sculptur Categories: Disambiguation ... An Altazimuth or alt-azimuth mount is a simple mount used for moving a telescope or camera along two perpendicular axes of motion. ... Capitals Las Palmas de Gran Canaria Santa Cruz de Tenerife Area  â€“ Total  â€“ % of Spain Ranked 13th  7 447 km²  1,5% Population  â€“ Total (2003)  â€“ % of Spain  â€“ Density Ranked 8th  1 843 755  4,4%  247,58/km² Demonym  â€“ English  â€“ Spanish  Canary Islander (Canarian)  canario/a Statute of Autonomy August 16... This article is about the European Space Agency. ... A space observatory is any object in outer space which is used for observation of distant planets, galaxies, and other outer space objects. ... The Herschel Space Observatory is a proposed mission of the European Space Agency. ... The 1960s, or The Sixties, in its most obvious sense refers to the decade between 1960 and 1969, but the expression has taken on a wider meaning over the past twenty years. ... The Anglo-Australian Observatory is an optical astronomy observatory located in the Warrumbungles National Park, near the town of Coonabarabran, Australia. ... The Northern Hemisphere is the half of a planets surface (or celestial sphere) that is north of the equator (the word hemisphere literally means half ball). On Earth, the Northern Hemisphere contains most of the land and population. ... 1974 is a common year starting on Tuesday (click on link for calendar). ... 1979 is a common year starting on Monday. ... 1981 is a common year starting on Thursday of the Gregorian calendar. ... Atmospheric characteristics Atmospheric pressure 120 kPa Hydrogen 83% Helium 15% Methane 1. ... Sir Wilhelm Friedrich Herschel (Hanover, November 15, 1738 – August 25, 1822 Slough, then in Buckinghamshire now in Berkshire) was a German-born British astronomer and composer who became famous for discovering the planet Uranus, and made many other astronomical discoveries. ... The Isaac Newton Group of Telescopes or ING operates the WHT, INT and JKT for PPARC, the NWO and the IAC. The Group is located on La Palma in the Canary Islands. ...

Construction began in 1983, and the telescope was shipped to La Palma in 1985. It saw first light in 1987. The telescope has an altazimuth mount. The mirror is maintained so that its theoretical maximum resolution is less than 0.2 arcseconds. The typical seeing at La Palma is of the order of one arcsecond, so the telescope is limited by that. 1983 is a common year starting on Saturday of the Gregorian calendar. ... 1985 is a common year starting on Tuesday of the Gregorian calendar. ... The first light is the moment when a telescope is first used to take an astronomical image after its construction. ... 1987 is a common year starting on Thursday of the Gregorian calendar. ... An Altazimuth or alt-azimuth mount is a simple mount used for moving a telescope or camera along two perpendicular axes of motion. ... Resolving power is the ability of a microscope or telescope to measure the angular separation of images that are close together. ... A second of arc or arcsecond is a unit of angular measurement which comprises one-sixtieth of an arcminute, or 1/3600 of a degree of arc or 1/1296000 ≈ 7. ... The word seeing can mean more than one thing: In common usage, the word means visual perception In astronomy, seeing is a technical term related to the clarity of the atmosphere In the occult seeing refers to the sight or the ablity to see auras or to predict the future...

As one of the best telescopes in the world, the WHT is heavily over-subscribed, and typically three times more applications for telescope time are received than can be accommodated. Notable discoveries made using the WHT include that of a hot bubble of expanding gas at the centre of the galaxy, suggestive of the presence of a supermassive black hole; the first observation of the optical counterpart of a gamma-ray burst; and recently, the discovery of a Wolf-Rayet star with the fastest-known stellar wind. This article is about a celestial body. ... A black hole is a concentration of mass great enough that the force of gravity prevents anything from escaping from it except through quantum tunneling behavior. ... In astronomy, gamma-ray bursts (GRBs) are flashes of gamma rays that last from seconds to hours, the longer ones being followed by several days of X-ray afterglow. ... Wolf-Rayet stars (often referred to as WR stars) are evolved, hot, massive stars, that have very strong stellar winds. ... A solar wind is a stream of particles (mostly high-energy protons ~ 500 keV) which are ejected from the upper atmosphere of a star (in the case of a star other than the Earths Sun, it may be called a stellar wind instead). ...

External link

• WHT Homepage
• WHT at Google Maps