The GTC is operated by a consortium of four institutions: the Institute of Astrophysics of the Canary Islands, the National Autonomous University of Mexico, the National Institute of Astrophysics, Optics, and Electronics of Mexico, and the University of Florida. Construction of the GTC began in 2000 it made its first observation in 2007. The telescope is mounted in a system that moves both in altitude and in azimuth to observe any point in the sky. This easy 60-minute walking tour around Siding Spring Observatory retraces the history of the observatory and includes a visit inside Australias largest. state of Hawaii. These two types of movements can compensate for the changes in the observed light that are caused by turbulence in Earth’s atmosphere. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. The mirror consists of 36 hexagonal pieces, which can be moved separately from each other, and the shape of each piece can be changed. It is located at the Roque de los Muchachos Observatory on La Palma (2,326 metres ) in the Canary Islands of Spain. This list of the largest optical reflecting telescopes with objective diameters of 3.0 metres (120 in) or greater is sorted by aperture, which is a measure of the light-gathering power and resolution of a reflecting telescope. Gran Telescopio Canarias (GTC), the largest optical telescope in the world, with a mirror that has a diameter of 10.4 metres (34.1 feet).

Largest optical telescope