The Nicholas U. Mayall Telescope, also known as the Mayall 4-meter Telescope, is a four meter reflector telescope located at the Kitt Peak National Observatory and named after Nicholas U. Mayall. It saw first light on February 27, 1973. Initial observers included: D. Crawford, Nicholas Mayall, and Arthur Hoag. It was dedicated on June 20, 1973 after Mayall's retirement as director. The mirror has an f/2.7 hyperboloidal shape. It is made from a two foot (61 cm (24 in)) thick fused quartz disk that is supported in an advanced-design mirror cell. The prime focus has a field of view six times larger than that of the Hale reflector.