Post by Andrei Tchentchik on Aug 14, 2020 10:33:18 GMT 2
(.#461).- A second collision of neutron stars has been detected! 2020.
A second collision of neutron stars has been detected!
By: Brice Louvet, science editor
January 7, 2020, 11:44 a.m.
Artist's illustration of two colliding neutron stars.
Credits: NASA / Swift / Dana Berry
A team of astronomers announces the detection of a second collision of neutron stars in a distant galaxy.
The first detection of a fusion of two neutron stars produced at about 130 million light-years ago took place in August 2017. It had been declared "scientific discovery of the year" by the journal Science. And for good reason, the observation of this phenomenon had made it possible to simultaneously capture gravitational and electromagnetic waves, thus opening a whole new window in the field of astrophysics.
A second event
And that was just the start. Last April, astronomers indeed recorded the gravitational waves testifying to a second event much more distant, at approximately 520 million light years.
Unlike the first event, however, no light could be detected for two simple reasons. The collision was probably too far away and one of the two LIGO detectors was offline when the event was recorded.
Artist's illustration of the GW190425 system.
Credits: National Science Foundation / LIGO / Sonoma State University / A. Simonnet
A new heavy object
Due to this lack of information, astronomers were unable to trace the exact source of this system, dubbed GW190425. At most, they managed to narrow the region where the signal was to come from a band covering about 20% of the sky. On the other hand, the gravitational waves captured made it possible to estimate the mass of the two objects concerned. Thus we learn that one of the neutron stars was 1.4 times more massive than the sun and the other was about twice as massive. This is a real surprise for the researchers.
"The total mass of this ancient binary system, which is about 3.4 times more massive than our Sun, far exceeds the mass of the binaries of known neutron stars in our own galaxy," says Susan Scott, of the 'Australian National University. "This leads to the intriguing possibility that this ancient system was formed differently from those observed in the Milky Way."
Remember that the two neutron stars involved in the 2017 event had masses between 1.1 and 1.6 solar masses.
Astronomers have not yet been able to determine the nature of the object resulting from this new collision. Indeed, we have never detected a black hole less than five times the mass of the sun, nor a neutron star more massive than about 2.5 times the mass of the sun. This new object being as heavy as 3.4 suns, we do not know if it is a small black hole or a large neutron star.
F I N .
A second collision of neutron stars has been detected!
By: Brice Louvet, science editor
January 7, 2020, 11:44 a.m.
Artist's illustration of two colliding neutron stars.
Credits: NASA / Swift / Dana Berry
A team of astronomers announces the detection of a second collision of neutron stars in a distant galaxy.
The first detection of a fusion of two neutron stars produced at about 130 million light-years ago took place in August 2017. It had been declared "scientific discovery of the year" by the journal Science. And for good reason, the observation of this phenomenon had made it possible to simultaneously capture gravitational and electromagnetic waves, thus opening a whole new window in the field of astrophysics.
A second event
And that was just the start. Last April, astronomers indeed recorded the gravitational waves testifying to a second event much more distant, at approximately 520 million light years.
Unlike the first event, however, no light could be detected for two simple reasons. The collision was probably too far away and one of the two LIGO detectors was offline when the event was recorded.
Artist's illustration of the GW190425 system.
Credits: National Science Foundation / LIGO / Sonoma State University / A. Simonnet
A new heavy object
Due to this lack of information, astronomers were unable to trace the exact source of this system, dubbed GW190425. At most, they managed to narrow the region where the signal was to come from a band covering about 20% of the sky. On the other hand, the gravitational waves captured made it possible to estimate the mass of the two objects concerned. Thus we learn that one of the neutron stars was 1.4 times more massive than the sun and the other was about twice as massive. This is a real surprise for the researchers.
"The total mass of this ancient binary system, which is about 3.4 times more massive than our Sun, far exceeds the mass of the binaries of known neutron stars in our own galaxy," says Susan Scott, of the 'Australian National University. "This leads to the intriguing possibility that this ancient system was formed differently from those observed in the Milky Way."
Remember that the two neutron stars involved in the 2017 event had masses between 1.1 and 1.6 solar masses.
Astronomers have not yet been able to determine the nature of the object resulting from this new collision. Indeed, we have never detected a black hole less than five times the mass of the sun, nor a neutron star more massive than about 2.5 times the mass of the sun. This new object being as heavy as 3.4 suns, we do not know if it is a small black hole or a large neutron star.
F I N .
