Hubble, with an 8 foot mirror, launched April 24, 1990, orbits at 375 miles above the earth. Following is a 3 year old tribute to the Hubble Space Telescope on its 20th anniversary in space. This beautiful video surveys the incredible accomplishments of this revolutionary instrument: everybody’s favorite telescope. (See also, Hubble Space Telescope – Wikipedia, the free encyclopedia).
Next Up and even more exciting: in early 2018 – The James Webb Space Telescope (sometimes called JWST) is a large, infrared-optimized space telescope. The project is working to a 2018 launch date. Webb will have a larger mirror, 6.5 meters (21.3 feet) in diameter and a sunshield the size of a tennis court. Both the mirror and sunshade won’t fit onto a rocket fully open, so both will fold up and open once Webb is in outer space. Webb will reside in an orbit about 1.5 million km (1 million miles) from the Earth. The James Webb Space Telescope will soar through space at the Second Sun-Earth Lagrange Point, an orbit far beyond Earth’s Moon. Webb’s giant sunshield will protect it from stray heat and light, while its large mirror enables it to effectively capture infrared light, bringing us the clearest picture ever of objects that emit this invisible radiation — early galaxies, just-forming stars, clouds of gas and dust, and much more.
Webb has an ambitious design that tackles the two main challenges for an infrared telescope: it has to have a large mirror, in order to best capture the long infrared wavelength; and it has to be kept cold, in order to keep unwanted sources of infrared from interfering with the emissions it attempts to detect. (See also: James Webb Space Telescope – Wikipedia, the free encyclopedia).