Mount Wilson Observatory is an astronomical observatory in southwestern California. It stands on Mount Wilson, 5,710 feet (1,740 meters) above sea level, about 10 miles (16 kilometers) northeast of Pasadena.
George Ellery Hale, an American astronomer, founded the observatory in 1904. It originally specialized in the study of the sun and is still a leading center for research on the magnetic fields and the velocities of the solar surface. The observatory has two solar telescopes, which are mounted in towers 150 and 60 feet (46 and 18 meters) high.
The observatory also operates two reflecting telescopes, one with a diameter of 60 inches (1.5 meters) and the other with a diameter of 100 inches (2.5 meters). These instruments are used to study stars. American astronomer Edwin P. Hubble used the 100-inch reflecting telescope to discover the expansion of the universe (see Universe (Size of the universe) ).
Until 1980, the Mount Wilson Observatory was operated jointly by the Carnegie Institution of Washington, D.C., and the California Institute of Technology at Pasadena. In 1980, the Carnegie Institution assumed sole administrative control of the Mount Wilson Observatory. The Carnegie Institution continued to operate the observatory until 1989. That year, administrative control of the observatory was transferred to the Mount Wilson Institute, a private organization. In 1995, the 100-inch telescope became the first large telescope in the United States to be fitted with an adaptive optics system to reduce atmospheric blurring.
