LIGO Laboratory, which has completed a major upgrade earlier this year, is preparing to start its first observing run. As a part of the preparation, LIGO will be undergoing final tests of its hardware and software systems during the month of August. On August 17, LIGO instruments at LIGO Hanford and LIGO Livingston will be fired up for a week for a prerun fine-tuning. Then on September 14, 2015, the 1st observing run will begin. It will last 3 months, during which the instruments at both locations will be running data collection around the clock.
Read more about preparatios to first observations at the LIGO Laboratory website.