Multiple Mirror Telescope
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Multiple Mirror Telescope(MMT) A reflecting telescope of novel design, sited at the Fred L. Whipple Observatory, on Mount Hopkins, near Tucson, Arizona at an altitude of 2600 meters. It was fully operational in 1980. The telescope, a joint project of the Smithsonian Institution and the University of Arizona, was in 1998 converted to a single-mirror instrument of diameter 6.5 meters (see MMT).
The original telescope was equivalent in light-gathering power to a single 4.5-meter mirror. It comprised six identical mirrors, 1.8 meters in diameter, arranged symmetrically about a central axis on an altazimuth mounting. A complex alignment and electronic guidance system brought all six images to a common focus, with one focus for optical work and another for infrared. The system was housed in a building that co-rotated on a rail with the telescope.