Multimessenger Astronomy with GW
On August 17th 2017 the LIGO-Virgo interferometers detected a gravitational wave signal from a neutron star merger that was found about 11 hours later in the galaxy NGC 4993: GW170817 is the first merger of two neutron stars ever detected. The presence of three detectors and the strength of the observed signal allowed estimating the approximate position in the sky of the source with enough precision and sending an alert to telescopes across the electromagnetic spectrum. Over 70 telescopes were pointed in the direction of the source and for many days they continued to observe the various signals emitted by the merger through its evolution.
The observation of kilonova GW170817 provided important scientific information on these never before observed phenomena, such as the first experimental proof that the heaviest elements in the periodic table are produced in neutron star mergers. This specific kilonova produced a mass of heavy elements about 16,000 times that of planet Earth.