LiGO’s agency announced that it had detected gravitational waves from a pair of neutron stars colliding,media reported. This marks the second discovery of such an event. Gravitational waves have been detected dozens of times since 2015, stemming from huge collisions that produce enough energy to distort the structure of space-time. As these ripples pass through Earth, detectors like LIGO and Virgo can detect them and determine their origin.
So far, most of the probes have come from the merger of black hole pairs, but scientists have also observed that black holes absorb neutron stars and collide with two neutron stars. Now, the last type of event is found again.
In August 2017, astronomers used LIGO in the United States and Virgo in Italy to detect the gravitational waves for the first time. The latest was in April 2019, and unfortunately there were no signals at the time, but it did deepen the understanding of gravitational waves.
Jo van den Brand, one of the study’s authors, said: “We found a second event that matched the dual neutron star system, which is an important confirmation of the August 2017 event. The event two years ago marked a new beginning in exciting multi-messenger astronomy. “
Interestingly, this probe is done only by a gravitational wave detector, LIGO Livingston. At the time, its partner, LIGO Hanford, was offline, and Virgo was too weak to receive the signal. Typically, researchers need several devices to triangulatthe the location of a signal, but in this case, the team was able to use non-detection to infer the general direction of the signal.
One strange difference for the 2019 test is that the new neutron stars produced in the collision are much larger than usual, about 3.4 times the mass of the sun, while most other planets have a maximum mass of 2.9 times that of the sun.
The study was published in Astrophysical Journal Letters.