Europe's William Herschel Telescope – completed in 1987 - is located on the island of La Palma in the Canary Islands. When it was built, its 4.2m mirror made it the third largest telescope in the world.
One of the first images of the surface of a star other than the Sun was made using this telescope. Observations carried out with the telescope strengthened the evidence that there is a supermassive black hole at the centre of the Milky Way.
Image: Composite picture of WHT and the setting Moon over the Atlantic Ocean (credit: Nik Szymanek and Robert Dalby/ING)
This European telescope is located on La Palma.
Patrick Moore's guest reviews the world's large observatories.
Sir Patrick Moore's guest Professor Richard Ellis from the University of Oxford reviews the world's large observatories and explains their importance. [The black and white images of Edwin Hubble, George Hale, Mount Wilson, the 200-inch telescope and mirror making in this clip are copyright Palomar Observatories/Caltech]
John Baldwin explains how he created an image of a star's surface.
Professor John Baldwin describes a novel technique that can be used to see the surface of a nearby star.
Patrick Moore and his guest discuss a new discovery.
Professor Michael Rowan-Robinson tells Sir Patrick Moore about a discovery made using the William Herschel Telescope. Rowan-Robinson also explains how the telescope is operated.
Patrick Moore meets an astronomer using the William Herschel Telescope.
Professor John Baldwin describes how he uses the William Herschel Telescope to build up a picture of the surface of a star.
Michael Rowan-Robinson talks about his work with the William Herschel Telescope.
Professor Michael Rowan-Robinson tells Sir Patrick Moore how he studies galaxies using the William Herschel Telescope and explains the implications of some of his findings.
The William Herschel Telescope (WHT) is a 4.20-metre (165 in) optical/near-infrared reflecting telescope located at the Observatorio del Roque de los Muchachos on the island of La Palma in the Canary Islands, Spain. The telescope, which is named after William Herschel, is part of the Isaac Newton Group of Telescopes. It is funded by research councils from the United Kingdom, the Netherlands and Spain.
At the time of construction in 1987, the WHT was the third largest single optical telescope in the world.[note 1] It is currently the second largest in Europe,[note 2] and was the final telescope constructed by Grubb Parsons in their 150-year history.
The WHT is equipped with a wide range of instruments operating over the optical and near-infrared regimes. These are used by professional astronomers to conduct a wide range of astronomical research. Astronomers using the telescope discovered the first evidence for a supermassive black hole (Sgr A*) at the centre of the Milky Way, and made the first optical observation of a gamma-ray burst.