On top of Mt. Hopkins, located some 40 miles south of Tucson, Arizona, a new telescope is now approaching completion. This telescope is the largest or third largest in the world, depending on whether one considers diameter or collecting area as the important characteristic of an optical telescope. This instrument, named the Multiple Mirror Telescope (MMT) because of its six-fold array of optical apertures, represents the first full-scale attempt to build an aperture-array telescope for general-purpose use.
by R. R. Shannon