A neutron star collision emitted a fast radio burst

Both this and the gravitational waves arrived at Earth practically at the same time

A collision between neutron stars could have emitted two different types of cosmic signals. On the one hand, gravitational waves, rips in space-time, but also a small burst of energy known as a fast radio burst. The two also arrived on Earth almost at the same time and were detected on April 25, 2019. The difference, in fact, as explained by a team of astronomers in ‘Nature Astronomy’, was two and a half hours despite that, before, they had traveled 370 million light-years.

A possible explanation for the fast radio bursts
If so, this discovery would support the theory that fast radio bursts may have multiple origins, including neutron star mergers. However, scientists admit that they are ‘only’ 99.5% sure that both signals have the same origin. Fast radio bursts have been picked up by the hundreds since the 2000s, but even so, the causes are unknown. Astrophysicists believe that they can come from highly magnetized neutron stars (magnetars), but since some are repeated and others only happen once, it seems that they could have different causes. One of them could be, for example, the collision of two neutron stars.

A neutron star merger at the limit of physics
Searching for data from signals arriving at the same time, the researchers found these two and, in addition, they were able to establish that the distance from which they came was the same. Also, gravitational waves were the only ones in that series of observations, and the burst was especially powerful. In fact, based on satellite data, there could even have been a gamma-ray burst, another known consequence of neutron star mergers. This combination, then, strongly points to this phenomenon as the source of the fast radio burst, which could have important implications.

One of them is, for example, that two neutron stars could merge and form a fatter one instead of immediately collapsing and forming a black hole, since the border between the two bodies is blurred. Although the fattest that has ever been detected is about 2.35 times the mass of the Sun, it is believed that it could become up to 3 strokes more massive without collapsing. In this case, if the 2019 collision had produced a neutron star, it would have been about 3.4 solar masses.