In 1916, Albert Einstein predicted that violent cosmic motions should send gravitational waves rippling through the fabric of space. This week, researchers inaugurated an unusual observatory designed to catch those elusive waves. The $292 million Laser Interferometer Gravitational-Wave Observatory (LIGO)--which has facilities in Livingston, Louisiana, and Hanford, Washington--will use laser beams to continually measure the positions of mirrors suspended in vacuum tubes 4 kilometers apart. Researchers hope the delicate detectors can discern relative wiggles as small as 1/10,000th the diameter of a proton.
"I can't imagine a more exciting new window to open on the universe," says Caltech physicist Gary Sanders, LIGO's deputy director. But LIGO probably won't sense any shimmers in space-time until both facilities are fine-tuned and ready to start eyeing the gravitational universe in early 2002.
