LIGO Resumes Hunt for Universe's Secrets with Enhanced Sensitivity.

The Laser Interferometer Gravitational-Wave Observatory (LIGO) has begun an 18-month campaign to detect the most distant collisions between black holes and neutron stars ever observed. Upgrades to LIGO's detectors mean they can measure gravitational waves emitted from colliding black holes in galaxies more than 5 billion light-years from Earth. LIGO's two US facilities will be joined by the Virgo detector in Italy and the Kamioka Gravitational Wave Detector in Japan. The hunt for gravitational waves will be extended into a worldwide effort.