Detection of an optical counterpart to a binary neutron star merger
The milestones just keep coming this year for the burgeoning field of gravitational wave astronomy. Closely following the first "triple coincidence" detection of a black hole merger (with the two LIGO instruments joined by the Italian Virgo instrument), comes the announcement yesterday of the first detection of a binary neutron-star merger, which was — spectacularly — accompanied by a gamma-ray transient detected by Fermi GBM. Things just got more exciting when an optical counterpart was detected for the gamma-ray and gravitational-wave source, with the Swope Telescope in Chile. The counterpart, named SSS17a, was subsequently followed by an estimated 70 different observational groups (including a range of Australian facilities coordinated via the OzGRav Centre of Excellence). A literal frenzy of activity followed, culminating in the LIGO press release in the early hours (Australian time) yesterday, and followed by our own press event at Old Parliament House yesterday morning. It is hard to quantify the impact of this event; the announcement was accompanied by an estimated 76 papers (with likely more to come). Sadly, our own GOTO telescope missed out on this event, but the optical brightness indicates that future events will be easily detectable, and validates our instrumental design. The prospects for additional detections when O3 begins (in late 2018) are excellent.