Hubble is the only telescope designed to be serviced in space by astronauts. After launch by Space Shuttle Discovery in 1990, four subsequent Space Shuttle missions repaired, upgraded, and replaced systems on the telescope. A fifth mission was canceled on safety grounds following the Columbia disaster. However, after spirited public discussion, NASA administrator Mike Griffin approved one final servicing mission, completed in 2009. The telescope is still operating as of 2014, and may last until 2020.[6] Its scientific successor, the James Webb Space Telescope (JWST), is currently scheduled for launch in 2018. Since the start of the program, a number of research projects have been carried out, some of them almost solely with Hubble, others coordinated facilities such as Chandra X-ray Observatory and ESOs Very Large Telescope. Although the Hubble observatory is nearing the end of its life, there are still major projects scheduled for it. One example is the upcoming Frontier Fields program,[90] inspired by the results of Hubbles deep observation of the galaxy cluster Abell 1689. The program, officially named Hubble Deep Fields Initiative 2012, is aimed to advance the knowledge of early galaxy formation by studying high-redshift galaxies in blank fields with the help of gravitational lensing to see the faintest galaxies in the distant universe.[90] The Frontier Fields web page describes the goals of the program being: to reveal hitherto inaccessible populations of z = 5 - 10 galaxies that are 10 to 50 times fainter intrinsically than any presently known to solidify our understanding of the stellar masses and star formation histories of sub-L* galaxies at the earliest times to provide the first statistically meaningful morphological characterization of star forming galaxies at z > 5 to find z > 8 galaxies stretched out enough by cluster lensing to discern internal structure and/or magnified enough by cluster lensing for spectroscopic follow-up.[94]
Posted on: Tue, 05 Aug 2014 10:42:39 +0000
Recently Viewed Topics
© 2015