Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Named after American astronomer Edwin Hubble, the Hubble Space telescope is a 2.4 meter aperture telescope put into low Earth orbit by the Space Shuttle mission STS-31 in 1990. Its orbit outside the distortion of Earth's atmosphere allows it to take extremely sharp images - Hubble's Ultra-Deep Field image, for instance, is the most detailed visible-light image ever made of the universe's most distant objects. Many of Hubble's observations have led to major breakthroughs in astrophysics, such as accurately determining the rate of expansion of the universe. Learn more about one of the most important scientific tools in the history of space exploration, the Hubble Space Telescope, its operators, on-bord instruments, as well as Hubble's eventual successor, the James Webb Space Telescope, in this book.