An observatory at an altitude of 1706 m, 80 km northeast of San Diego, California, owned and operated by the California Institute of Technology (Caltech), Pasadena. It was founded in 1934 but completion was delayed by World War II. Its main instrument is the 200-inch (5-m) Hale Telescope opened in 1948, named after the observatory’s founder, G. E. Hale. Also in operation since 1948 has been the 1.2-m Oschin Schmidt Telescope, named after Samuel Oschin, a benefactor of the observatory, used for the Palomar Observatory Sky Survey (POSS); a new corrector plate was installed in 1985. Also on the mountain is a 1.5-m reflector opened in 1970. A 0.46-m Schmidt, opened in 1936 as the first telescope at the observatory, was closed in 1995.

http://www.astro.caltech.edu/palomar/ Official observatory website.