(1868-1938) US astronomer who made pioneer studies of the Sun and founded three major observatories. In 1889 he invented the spectroheliograph, a device for photographing the Sun at particular wavelengths. In 1917 he established on Mount Wilson, California, a 2.5-m/100-in reflector, the world's largest telescope until superseded 1948 by the 5-m/200-in reflector on Mount Palomar, which Hale had planned just before he died.
In 1897 he founded the Yerkes Observatory in Wisconsin, with the largest refractor, 102 cm/40 in, ever built at that time.
Hale was born in Chicago and studied at the Massachusetts Institute of Technology. In 1892 he became professor at Chicago, moving to Mount Wilson as director 1904–23. He was elected to the governing body of Throop Polytechnic Institute in Pasadena, and through his influence this developed into the California Institute of Technology.
Hale's work on solar spectra was the stimulus for his construction of a number of specially designed telescopes. By studying the split spectral lines of sunspots, he showed the presence of very strong magnetic fields—the first discovery of a magnetic field outside the Earth. In 1919, he showed that these magnetic fields reverse polarity twice every 22–23 years. + prikaži više