Concrete and stainless steel tubes house and protect the four-kilometer
long laser apparatuses at the LIGO Hanford Observatory in Hanford,
Washington, January 9, 2002. LIGO, which stands for Laser
Interferometer Gravitational-Wave Observatory, has the mission to
observe gravitational waves of cosmic origin, including those created
by black holes, star collisions and remnants of gravitational radiation
created by the "big-bang" birth of the universe. The LIGO Hanford
facility houses laser interferometers consisting of mirrors suspended
at each of the corners of a gigantic L-shaped vaccum system measuring
four kilometers on each side. LIGO Hanford is part of a $370 National
Science Foundation project focused at researching these gravitational
waves. REUTERS/Anthony P. Bolante/FEATURE-SCIENCE-GRAVITY

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