The Hubble Space Telescope was launched aboard the STS-31 mission of the Space Shuttle Discovery on April 24, 1990. Within a few months, a flaw was discovered in Hubble's main mirror and this significantly reduced the telescope's ability to focus. In December, 1993; February, 1997; and December 1999, astronauts conducted Hubble servicing missions to bring the telescope to full capability.
The Hubble Space Telescope was named by NASA in honor of astronomer Dr. Edwin Powell Hubble (1889-1953). Hubble determined that galaxies (very large groups of stars and associated matter) exist outside of and are receding from the Milky Way. His work demonstrated that the universe is expanding.
