The William Herschel Telescope

The William Herschel Telescope is currently the largest telescope in the Canary Isles, and indeed throughout the whole of Western Europe. As La Palma is part of Spain, it is considered part of Europe.

William Herschel Telescope © ING

Some facts about the telescope: Observatory location: La Palma, Canary Isles Height above sea level: 2,332 metres (7,650 feet) Moving Mass: 210 metric tonnes Mirror diameter: 4.2 metres

This magnificant telescope is housed in a purpose built enclosure. Because the telescope is so complex, it requires engineers and scientists to be available in case any of the systems break. As such, an attached building is needed to house offices, workshops, toilets etc. This is the reason the telescope enclosure is so large.

The observatory building also contains an aluminising plant which is used to re-aluminise the mirror (replacing the mirror's reflective surface) approximately once a year.

Over this period, dust and other contaminants reduce the mirror's reflectivity, lowering its performance and hence the light gathering power of the telescope.

The control room is the nerve centre of the observatory.

Each evening astronomers make their way to this room, and spend all night here as they observe various objects throughout the Universe.

 

Images taken by the William Herschel Telescope

 

For some years now satellites have been detecting bursts of gamma rays (GRBs) from space. No one could identify from where this radiation was coming. On February 28, 1997 the William Herschel telescope took the first picture of the source of a GRB. This point of light is probably the most powerful explosion mankind has ever witnessed. GRBs were discovered in the early seventies and their origin has remained unsolved since then. Look carefully close to the M dwarf star. You will notice a brightening in the left-hand picture which was gone a week later (right-hand image). This was the Gamma Ray Burst. Note that the image is in negative (i.e. black and white reversed). Thanks to this picture, and later investigations, we now know that these explosions take place outside our galaxy (Milky Way). Nevertheless fundamental questions such as the origin of the events, the source of energy, the triggering mechanism and the radiation processes still remain to be determined.

Gamma Ray burst caught on film Click here for larger image

Looking towards the edge of the known Universe

A true-colour image of faint blue galaxies at the edge of the observable Universe.

To gather enough light to take this remarkable picture the telescope had to look at the night sky for 30 hours.