The Gran Telescopio Canarias is a 10.4 m (410 in) reflecting telescope undertaking commissioning observations at the Roque de los Muchachos Observatory on the island of La Palma. As of 2009, it is the world’s largest single-aperture optical telescope.
There is a gallery of astronomical images where it can be seeing the kind of images acquired by the telescope. The images are representations in color of the received data. The colors are assigned using different schemes. Usually it depends on the data they want to represent although sometimes they use purely aesthetic criteria.