Before the Monday event, everyone predicted that there would be an announcement regarding yet another, probably the fifth detection of gravitational waves by LIGO and Virgo, just like it was announced on September 27.
But on October 16, LIGO revealed something astonishing. It announced that scientists at the LIGO detectors, with the help of Virgo as well as other observatories, successfully detected the first ripples in space or gravitational waves which are generated by the merger of two ancient remnants of stars called as neutron stars. The scientists informed that the neutron stars merged in a galaxy called NGC 4993, located about 130 million light-years away from Earth in the constellation Hydra.
Seven new papers related to gravitational wave detection and research revealed the first ever detection of light from a gravitational wave source. The phenomenon of collision and merger of two neutron stars was termed as “GW170817” as it sent ripples through space-time that reached our Earth on August 17. The excited astronomers present all over the world mobilized quickly and observed the never-seen-before event through their telescopes thus gather a lot of new data.
The event was special because all the previous detection of gravitational waves were found to be emerging out from the merger of two black holes. This was the first time scientists detected the gravitational waves produced by the merger of two neutron stars. As because the black hole mergers do not produce electromagnetic radiation, so they cannot be detected by conventional telescopes. But the neutron star merger emits light having electromagnetic radiation, so they were successfully observed by astronomers with the help of conventional telescopes. Professor Ehud Nakar of Tel Aviv University’s Raymond and Beverly Sackler School of Physics and Astronomy said that this event is a milestone in the growing effort by scientists worldwide to unlock the mysteries of the universe and the Earth. Actually, a Neutron star is formed when a star much bigger and brighter than the sun exhausts its thermonuclear fuel supply and explodes into a violent supernova.
The multiple telescopes detected the gamma rays, visible light and radio waves of electromagnetic radiations produced by the explosion. First LIGO detected the gravitational waves and then Virgo detected the ripples. Then after two seconds the Gamma-ray Burst Monitor on NASA’s Fermi Gamma-ray Space Telescope detected a short burst of gamma rays. So, analyzing all these, scientists concluded that gravitational waves are coming out from the merger of neutron stars.