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GranTeCan Telescope

The Gran Telescopio Canarias, also known as GranTeCan or GTC, is a 10.4 metre telescope, which began operations in 2009. The GTC Project is a partnership between Spain, Mexico, the University of Florida and the Instituto de Astrofísica de Canarias (IAC).

GranTeCan Telescope - © GTC

The large mirror makes GranTeCan the second largest reflecting telescope in the world. However, its mirror is actually composed of 36 hexagonal segments that work together as one reflective unit and can be computer controlled to overcome poor observing conditions.

Some facts about the telescope:

  • Observatory location: La Palma, Canary Isles
  • Height above sea level: 2,267 metres (7,440 feet)
  • Moving Mass: 500 metric tonnes
  • Mirror diameter: 10.4 metres
The telescope has cost around £110 million to build, but the first images from the telescope clearly show the benefits of such a large and sophisticated telescope.
Image of M51 - © GTC/OSIRIS

So far there are two main instruments attached; namely the OSIRIS optical light camera and the CanariCam infrared camera.

This beautiful image is a three-colour composition of M51, the Whirpool galaxy. Located 23 million light-years away, this magnificent spiral was observed using the OSIRIS camera on the GTC, with an exposure time of 120 seconds. To reach a similar depth using a 1m telescope, an exposure time of more than three hours would be required.


Please note that over the weekend of the 26-29th May 2017 we will be switching over to our brand new website - during this time there may be periods where the site is difficult to access, and users will be unable to request observations from the telescope. Please bear with us during this time. All should be back up and running by the 30th May 2017.