\"Mayall 4-meter Telescope\" Nicholas Mayall Hand Signed 3X3 B&W Photo For Sale

Up for sale a RARE! "Mayall 4-meter Telescope" Nicholas U. Mayall Signed 3X3 B& W Photo. 

ES-6222E

The Nicholas U.

Mayall Telescope, also known as the Mayall 4-meter Telescope,

is a four-meter (158 inches) 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 (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. 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.