Participants of the LIGO / VIRGO collaboration have registered a new gravitational wave, formed as a result of the merger of two black holes, and it was recorded by three detectors at once, including the recently launched VIRGO detector in Italy. This is already the fourth case of gravitational waves fixation, but in all previous cases they were registered by only two LIGO detectors. This is reported by a press release from LIGO.
According to the representative of the LIGO / VIRGO collaboration, they managed to record a gravitational wave, the source of which was the collision of two black holes with masses of about 31 and 25 solar masses, which occurred at a distance of 1.8 billion light years from Earth. As a result of this merger, a rotating black hole with a mass of about 53 solar masses was formed. Signal GW170814 was recorded on August 14 at 14:51 Moscow time. According to scientists, receiving a signal at once to three detectors will help them calculate more accurate coordinates of its source. Already, based on the time delay in receiving the signal, which was 7 milliseconds for the two LIGO detectors, scientists were able to determine that the source is in the southern hemisphere of the celestial sphere.
Based on the electromagnetic signals previously received by some telescopes, including the Hubble telescope, many expected that the source of the registered gravitational wave this time was the merger of two neutron stars, but these assumptions were not confirmed.
It is noteworthy that only at the beginning of August 2017, the two observatories joined forces and in less than two weeks were able to register the first signal.
Gravitational waves - waves of oscillations of space-time geometry. The existence of such waves is a direct consequence of the theory of relativity. They arise during the movement of any objects that have mass and move with acceleration, but they can be reliably registered only when very fast and massive objects interact. A gravitational wave can be formed as a result of interactions in binary systems: for example, when black holes or neutron stars merge. So far, all the gravitational waves that could be detected, both recorded in 2015 and 2017 on the detectors of the LIGO observatory, and recorded now, were formed just as a result of the merger of black holes.
Alexander Dubov