About Walter Baade
Wilhelm Heinrich Walter Baade was a German astronomer who worked in the United States from 1931 to 1959. In 1920 he discovered 944 Hidalgo, the first of a class of minor planets now called Centaurs which cross the orbits of giant planets. During World War II, while working at Mount Wilson Observatory, Baade took advantage of wartime blackout conditions (which reduced light pollution), to resolve stars in the center of the Andromeda Galaxy for the first time.
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