During its first observation run, on Sept. 14, 2015, just days after becoming fully operational, Advanced LIGO laser beams stretched just a bit more than usual. (discovermagazine.com)
This event, detected by the two NSF - supported LIGO detectors at 02:01:16 UTC on June 8, 2017 (or 10:01:16 pm on June 7 in US Eastern Daylight time), was actually the second binary black hole merger observed during LIGO's second observation run since being upgraded in a program called Advanced LIGO. (phys.org)
The Virgo detector, a third interferometer located near Pisa, Italy, with a design similar to the twin LIGO detectors, is expected to come online during the latter half of LIGO's upcoming observation run. (sciencedaily.com)