Hubble Space Telescope

The Hubble Space Telescope is a space telescope launched in 1990 that remains in operation, featuring a 2.4m mirror and observing in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Its orbit outside the Earth's atmosphere allows it to capture high-resolution images with lower background light than ground-based telescopes, leading to breakthroughs in astrophysics such as determining the rate of expansion of the universe. The telescope was initially plagued by technical delays and budget problems, but was finally launched in 1990 with a main mirror that had been ground incorrectly, resulting in spherical aberration. The optics were corrected in 1993 by a servicing mission, and the telescope has since been maintained and upgraded by five Space Shuttle missions. Hubble is predicted to last until 2030-2040 and is part of NASA's Great Observatories program, which also includes the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope.learn more on wikipedia