Hubble, Edwin P.

American Astronomer 1889-1953

American astronomer Edwin Powell Hubble's (1889-1953) key discovery was his finding that the universe is expanding.^* Hubble received undergraduate degrees in math and astronomy from the University of Chicago. Upon graduation, he was awarded a Rhodes scholarship to Oxford University, where he studied law. After some time as a lawyer and teacher, he returned to the University of Chicago to pursue a doctorate in astronomy. During his studies, World War I (1914 -1918) began. Hubble enlisted in the army and rose to the rank of major.

After the war, Hubble worked at Mount Wilson Observatory, California, which then contained the largest telescope in the world. In the early 1920s, scientists knew about our own galaxy, the Milky Way, but they did not know if anything was outside of it. Some had conjectured that nebulae, faint cloudy features in the night sky, were actually "island universes" or other galaxies. Hubble measured the distance to some of these nebulas and found that they indeed lay far outside the Milky Way. In further studies, he showed that these nebulas are actually other galaxies, and he went on to classify them.

After this work, he made the most remarkable discovery of his career. He found that the more distant the galaxy, the faster it is moving away from Earth. This relationship implies that the universe is expanding, and this knowledge led to the formation of the Big Bang theory describing the formation of the universe. The constant that describes the relationship between galaxy speed and distance is called the Hubble constant.

SEE ALSO ASTRONOMY, HISTORY OF (VOLUME 2); ASTRONOMY, KINDS OF (VOLUME 2); GALAXIES (VOLUME 2); HUBBLE CONSTANT (VOLUME 2); HUBBLE SPACE TELESCOPE (VOLUME 2).

Derek L. Schutt

Bibliography

Christianson, Gale E. Edwin Hubble: Mariner of the Nebulae. New York: Farrar, Straus, Giroux, 1995.

Sharov, Alexander S., and Igor D. Novikov. Edwin Hubble: The Discoverer of the Big Bang Universe, trans. Vitalie Kisin. Cambridge, UK: Cambridge University Press, 1993.

^*NASA's Hubble Space Telescope, launched in 1990, bears this noted astronomer's name.