The Reber Radio Telescope is a historic radio telescope, located at the Green Bank Observatory near Green Bank, West Virginia. Built in 1937 in Illinois by astronomer Grote Reber, it is the first purpose-built parabolic radio telescope.
Reber built a parabolic dish reflector because this shape focuses waves to the same focus for all wavelengths. This principle had been used for a long time by astronomers for design of optical telescopes, to avoid chromatic aberration. Reber knew that it would be important to observe a wide range of wavelengths of radiation from the sky in order to understand how the radiation was being produced. A parabolic reflector is usable over a wide wavelength range.
The Reber Radio Telescope is located on the grounds of the Green Bank Observatory (formerly part of the National Radio Astronomy Observatory) in rural Pocahontas County, West Virginia. It consists of a parabolic reflector composed of 72 radial rafters and covered in 26 gauge iron sheeting with a focal length of 20 feet (6.1 m). It is 31 feet 5 inches (9.58 m) in diameter, and is mounted on arched rails positioned on railroad wheels, allowing its angle of elevation to be controlled.
Reber Radio Telescope was listed on the National Register of Historic Places in 1972 and declared a National Historic Landmark in 1989.
According to greenbankobservatory.org; en.wikipedia.org. Source of photos: internet
