Another important finding in the science of astrophysics. For the second time, gravitational waves have been detected on Earth, that were most likely from a distant unusual catastrophic event, a two-star neutron collision.
The announcement was made by the US-Europe international research consortium of LIGO and VIRGO observatories.
The first detection of a similar origin for gravitational waves was in August 2017, in a galaxy 130 million light-years away from our planet. The second detection, over 500 million light-years away, was done only by the LIGO detector in Louisiana, as the second in Washington was temporarily disabled while the European in Pisa, Italy, was not sensitive enough to “catch” the light. signals.
Usually, the international network uses all three of its observatories to confirm a discovery, but this time it did not.
Most of the gravitational waves detected to date (beginning in 2015) are probably from colliding black holes rather than neutron stars. The latter are very dense remnants of devastated giant stars about the size of a city, which swirl swiftly and may sometimes merge with a similar neighboring star, which sends gravitational waves into space.
Scientists calculated that the total mass of the merging second pair of neutron stars was 3.4 times larger than our Sun. Up to now, pairs of neutron stars with a combined mass of up to 2.9 times larger than the Sun have been discovered in our galaxy.
“This is clearly heavier than any other pair of neutron stars that has ever been observed,” said Katerina Hadjiioannou, a Greek astronomer and a researcher with the Center for Computational Astrophysics at the New York Flatiron Institute’s Interferometer-Laser Observer at the American Astronomical Society’s annual convention in Honolulu, Hawaii. A related publication will follow in the astrophysical journal “The Astrophysical Journal Letters”, as quoted by the Athens-Macedonian News Agency.
She did not completely rule out the possibility of gravitational waves not coming from neutron stars, but from merging between two “light-weight” black holes (the smallest they would have ever found) or between a black hole and a neutron star. . As Hadjiioannou said, after the merging of the two star neutrons, they collided gravitationally, creating a black hole.
In any case, gravitational waves are increasingly paving the way for a new multimessenger astronomy, in which scientists have a variety of sources of information about the same phenomenon. Another relevant detector will soon be operational in Japan.