Two sites for catching gravitational waves.Situated on an arid plateau in central Washington state, the Department of Energy's vast Hanford Reservation has long served as a center for the extraction of plutonium from spent nuclear fuel Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant) to the point where it is no longer useful in sustaining a nuclear reaction. . Last week, the National Science Foundation (NSF) designated a site on the Hanford Reservation as one of two locations for the twin facilities of a unique, sophisticated observatory dedicated to the detection of a very different, much more elusive type of radiation - gravitational waves. The other chosen site lies in a flat, wooded area near Livingston, La., about 30 miles east of Baton Rouge. Following more than a decade of feasibility studies and political wrangling, this decision clears the way for construction of the Laser Interferometer Grvitational-Wave Observatory (LIGO). "Overall, I am convinced that the Louisiana-Washington sites will best serve the scientific objectives of this important project," says NSF Director Walter E. Massey For Walter Massey, the Canadian actor, see . Walter E. Massey, an American educator, physicist, and business leader, was born in Hattiesburg, Mississippi April 5 1938. Massey graduated from Morehouse College in 1958 and received his PhD from Washington University in St. , who made the decision. Consisting of two facilities separated by at least 2,400 kilometers but operating in unison to avoid false signals, the observatory will cost about $210 million and take five years to build. Last October, Congress approved $23.5 million in first-year funding to cover the costs of selecting the sites, completing the engineering design of the facilities and starting site preparation. The building of LIGO represents a bold gamble to detect the distinctive imprint of gravitational waves resulting from such violent cosmic events as the collapse of stellar cores and collisions between black holes. The project furnishes an important means of testing Einstein's general theory of relativity Noun 1. Einstein's general theory of relativity - a generalization of special relativity to include gravity (based on the principle of equivalence) general relativity, general relativity theory, general theory of relativity , in which massive bodies such as stars influence other objects not by acting on them directly but instead by warping space and time. When such a body abruptly changes its motion or its mass, the space-time in its vicinity undergoes a corresponding convulsion convulsion, sudden, violent, involuntary contraction of the muscles of the body, often accompanied by loss of consciousness. It is not known what causes the abnormal impulses from the brain that result in convulsive seizures, since the disturbance may arise in normal . This disturbance travels outward as a gravitational wave that jostles any objects in its path. To detect a gravitational wave passing through Earth, each LIGO facility will have two evacuated steel pipes, 4 feet in diameter and 2.5 miles long, extending at right angles so as to form a right angle or right angles, as when one line crosses another perpendicularly. See also: Right to each other. Laser light will pass up and down the pipes, bouncing between pairs of mirrors attached to heavy weights. A gravitational wave passing through the facility would imperceptibly move one set of weights closer together and the other farther apart. That slight change in the distance traveled by the laser beams in the two branches would show up as a shift in the interference pattern created where the two beams recombine re·com·bine v. To undergo or cause genetic recombination; form new combinations. . A tend of scientists from the California Institute of Technology California Institute of Technology, at Pasadena, Calif.; originally for men, became coeducational in 1970; founded 1891 as Throop Polytechnic Institute; called Throop College of Technology, 1913–20. in Pasadena, location of an experimental prototype facility, and the Massachusetts Institute of Technology Massachusetts Institute of Technology, at Cambridge; coeducational; chartered 1861, opened 1865 in Boston, moved 1916. It has long been recognized as an outstanding technological institute and its Sloan School of Management has notable programs in business, will oversee the construction and operation of the LIGO facilities. |
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