This article will be permanently flagged as inappropriate and made unaccessible to everyone. Are you certain this article is inappropriate? Excessive Violence Sexual Content Political / Social
Email Address:
Article Id: WHEBN0000583118 Reproduction Date:
19°49′35″N 155°28′30″W / 19.82636°N 155.47501°W / 19.82636; -155.47501
The W. M. Keck Observatory is a two-telescope astronomical observatory at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes feature 10 m (33 ft) primary mirrors, currently among the largest astronomical telescopes in use. The combination of an excellent site, large optics and innovative instruments has created one of the most scientifically productive astronomical observatories in the world.
With a concept first proposed in 1977, telescope designers at the University of California and Lawrence Berkeley Labs had been developing the technology necessary to build a large, ground based telescope. With a design in hand a search for the funding began. In 1985, Howard B. Keck of the W. M. Keck Foundation gave $70 million to fund the construction of the Keck 1 Telescope. Construction of Keck 1 began in September 1985, with first light occurring on 24 November 1990 using only nine of the eventual 36 segments. With construction of the first telescope well advanced, further donations allowed the construction of a second telescope starting in 1991. The Keck 1 telescope began science observations in March 1993, while first light for Keck 2 occurred in 23 January 1996.
The key advance that allowed the construction of the Keck's large telescopes was the ability to operate smaller mirror segments as a single, contiguous mirror. In the case of the Keck telescopes each of the primary mirrors is composed of 36 hexagonal segments that work together as a single unit. The mirrors were made from Zerodur glass-ceramic by the German company Schott AG.[2] On the telescope, each segment is kept stable by a system of active optics, which uses extremely rigid support structures in combination with three actuators under each segment. During observation, the computer-controlled system of sensors and actuators adjusts the position of each segment, relative to its neighbors, to an accuracy of four nanometers. This twice-per-second adjustment counters the effect of gravity as the telescope moves, in addition to other environmental and structural effects that can affect the mirror shape.
Each Keck telescope sits on an altazimuth mount. Most current 8-10m class telescopes use altazimuth designs due to the reduced structural requirements compared to older equatorial designs. This mounting style provides the greatest strength and stiffness for the least amount of steel, which, for Keck, totals about 270 tons per telescope. The total weight of each telescope is more than 300 tons. Two of the proposed designs for the next generation 30 and 40m telescopes use the same basic technology pioneered at Keck, a hexagonal mirror array coupled with an altazimuth mounting.
The primary mirrors of each of the two telescopes are 10 meters (32.8 ft (394 in)) in diameter, making them the second largest optical telescopes in the world, slightly behind the Gran Telescopio Canarias.
The telescopes are equipped with a suite of instruments, both cameras and spectrometers that allow observations across much of the visible and near infrared spectrum.
The Keck Observatory is managed by the California Association for Research in Astronomy, a non-profit 501(c)(3) organization whose board of directors includes representatives from Caltech and the University of California. Construction of the telescopes was made possible through private grants totaling more than $140 million provided by the W. M. Keck Foundation. The National Aeronautics and Space Administration (NASA) joined the partnership in October 1996, at the time Keck 2 commenced observations.
Telescope time is allocated by the partner institutions. Caltech, the University of Hawaii System, and the University of California accept proposals from their own researchers. NASA accepts proposals from researchers based in the United States, while the National Optical Astronomy Observatory (NOAO) accept proposals from researchers around the world.[3]
Both Keck telescopes are equipped with laser guide star adaptive optics, which compensates for the blurring due to atmospheric turbulence. The first AO system operational on a large telescope, the equipment has been constantly upgraded to expand the capability.
Big Bang, Hubble Space Telescope, Redshift, Milky Way, Solar System
South Africa, University of Wisconsin–Madison, United Kingdom, Korea, Germany
Mass, Greek mythology, Asteroid belt, Themis family, Density
Princeton University, Duke University, Mit, Harvard University, Johns Hopkins University