Hale, George Ellery

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Hale, George Ellery (1868-1938), American astronomer, born in Chicago, Illinois, and educated at the Massachusetts Institute of Technology. While Hale was still in college, his father built the Kenwood Observatory, a small observatory near Chicago. Hale used the observatory for original research and in 1889 invented the spectroheliograph, a device used to study the surface of the sun. In 1892 Hale was appointed associate professor of astrophysics at the University of Chicago and in 1895 he organized the Yerkes Observatory, in Williams Bay, Wisconsin, of which he served as director until 1904. In 1904 he organized the Mount Wilson Observatory, near Los Angeles, California, which he directed until 1923. In 1908, Hale discovered that sunspots have magnetic fields. Hale conceived and helped design the first giant reflecting telescope. The instrument, a reflector with a 200-in (5.08-m) mirror, was installed at Mount Palomar Observatory near San Diego, California, in 1948. It was named the Hale Telescope in his honor.

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