To catch a wave.

After decades of effort, physicists say they are on the verge of detecting ripples in spacetime called gravitational waves, whose existence Albert Einstein himself predicted nearly a century ago. Researchers working on the Laser Interferometer Gravitational-Wave Observatory (LIGO) will use enormous instruments in Livingston, Louisiana, and Hanford, Washington, to look for the gravitational waves set off when two neutron stars spiral into each other. LIGO ran from 2002 to 2010 and saw nothing, but those Initial LIGO instruments aimed only to prove that the experiment was technologically feasible, physicists say. Now, they9re finishing a $205 million rebuild of the detectors, known as Advanced LIGO, which should make them 10 times more sensitive and, they say, virtually ensure a detection. Such an observation would open up a whole new type of astronomy—and likely bag a Nobel Prize.