The Hubble Space Telescope (HST) is a space telescope that was launched into low Earth orbit in 1990, and remains in operation. Although not the first space telescope, Hubble is one of the largest and most versatile, and is well known as both a vital research tool and a public relations boon for astronomy. The HST is named after the astronomer Edwin Hubble, and is one of NASA's Great Observatories, along with the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope. . On April 24, 1990, shuttle mission STS-31 saw Discovery launch the telescope successfully into its planned orbit.
In 1946 American astrophysicist Lyman Spitzer was the first to conceive the idea of a telescope in outer space, 11 years before the Soviet Union launched the first satellite, Sputnik 1, in October 1957. Spitzer's proposal called for a large telescope that would not be hindered by Earth's atmosphere. After lobbying in the 1960s and 70s for such a system to be built. Spitzer's vision ultimately materialized into the Hubble Space Telescope. Although not the first space telescope, Hubble is one of the largest and most versatile and is well known as both a vital research tool.