Hubble, Edwin Powell (1889-1953), was an American astronomer whose work revolutionized our understanding of the size and structure of the universe. In the early 1900’s, many astronomers believed that all stars and other celestial objects were part of the Milky Way, the galaxy that contains our solar system. In the 1920’s, Hubble studied a hazy patch of the sky called the Andromeda Nebula. Hubble noticed that it contained stars resembling stars in the Milky Way but much fainter. He concluded that the stars in the nebula must be much farther from Earth than stars in our own galaxy. His work proved that the Andromeda Nebula was actually a distant galaxy separate from our own.
Hubble later studied the speed at which galaxies move away from each other. In 1929, he discovered that the farther apart galaxies are from each other, the faster they move away from each other. Based on this observation, Hubble concluded that the universe expands uniformly.
Hubble was born on Nov. 20, 1889, in Marshfield, Missouri. He earned a Ph.D. degree from the University of Chicago in 1917. In 1919, he joined the staff of the Mount Wilson Observatory in California, where he remained until his death on Sept. 28, 1953. The Hubble Space Telescope, launched by the National Aeronautics and Space Administration in 1990, was named in his honor.
See also Andromeda Galaxy; Galaxy; Hubble constant; Milky Way.
