Nicholas U. Mayall Telescope

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 in Arizona and named after Nicholas U. Mayall. It saw first light on February 27, 1973, and was the second-largest telescope in the world at that time. Initial observers included David 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 ) 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. It is host to the Dark Energy Spectroscopic Instrument. The identical Victor M. Blanco Telescope was later built at Cerro Tololo Inter-American Observatory, in Chile.
The telescope was dedicated in the summer of 1973, at which time it was the second largest telescope by aperture in the world. The telescope was named after Mayall who was the director of Kitt Peak National Observatory for over a decade.

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