DISCOVERY: ESO telescopes detect first visible counterpart to gravitational wave source. Observations suggest that the object is the result of the merger of two neutron stars.

The cataclysmic aftermath of this kind of merger — the long-predicted event called a Kilonova.

Kilonova disperse heavy elements such as gold and platinum throughout the Universe.

The discovery is evidence that mergers of neutron stars produce short-duration gamma-ray bursts.