Queen of Telescopes
The world's largest optical telescope, with a mirror diameter equivalent of 34 feet was inaugurated in the Canary Islands. On hand to open was Brian May, the guitarist of Queen, who is a PhD Candidate in Astronomy.
Currently, its adaptive optics system controls 12 hexagonal segments of the primary mirror for testing and observations. Later, when fully operational, the telescope will use 36 movable segments.
Observatorio de Roque de los Muchachos (translated as Observatory of Castle of the Boys) is an astronomical observatory that is operated by the Instituto de Astrofisica de Canarias (Canaries Astrophysics Institute), a part of the European Northern Observatory.
The second largest telescopes in the world, by usable mirror size, are the twin Keck telescopes on Mauna Kea, Hawaii, in the United States, which have mirror diameters that measure 10 meters (32.8 feet) across. It is interesting to note that the Hobby-Eberly Telescope, also in the United States—near Fort Davis, Texas in the southwestern part of the state—and the South African Large Telescope have larger mirrors but only a portion of each mirror is able to be used when making observations.