Ligo-Virgo announced four new gravitational wave detections from the second observing run, which lasted from November 30, 2016, to August 25, 2017. The four events all come from binary black hole collisions and are known as GW170729, GW170809, GW170818, and GW170823.
GW170729 is the most massive and distant gravitational wave source ever observed. In this event which happened at a distance of more than 5 billion light-years, two black holes of 51 and 34 solar masses collided to form a new black hole of 80 solar masses with a generation of 5 solar masses in gravitational radiation.
GW170809 refers to a collision of two black holes of 35 and 24 solar masses with the formation of one black hole of 56 solar masses with a generation of 3 solar masses in gravitational radiation.
GW170818 happened a distance of more than 2.5 billion light-years and was precisely pinpointed in the sky with an accuracy of 39 square degrees. In this event, two black holes of 36 and 27 solar masses collided to form a new black hole of 60 solar masses with a generation of 3 solar masses in gravitational radiation.
GW170823 refers to a collision of two black holes of 40 and 30 solar masses with the formation of one black hole of 66 solar masses with a generation of 4 solar masses in gravitational radiation.
CENTRA congratulates the Ligo and Virgo teams.