Gravitational wave observator using a laser interferometer (LIGO) in the U.S.
Scientists have first discovered black holes that eat neutron stars, “like Pac-Man,” in a discovery that documents the collision between the two most extreme and mysterious objects in the universe.
The gravitational wave observator using a laser interferometer (LIGO) in the US and the gravitational wave observatory Virgo in Italy captured the gravitational waves from the death spiral and merging of a neutron star with a black hole, and not once but twice. The findings were recently published in The Astrophysical Journal Letters.
Researchers say their observations will help solve some of the universe’s most complex mysteries, including the building blocks of matter and the modes of action of space and time.
More than a thousand scientists took part in the first discoveries in the world, with many of the leaders from Australia, including the National University of Australia (ANU).
Research professor Susan Scott of the ANU School of Physics Research at the Center for Gravitational Astrophysics, co-author of the study, said the events occurred about a billion years ago but were so massive we can still see their gravitational waves today.
“These collisions shook the universe from the ground up and we recognized the ripples they sent moving powerfully across the cosmos,” she said.
“Any collision like this is not just an encounter between two massive and dense objects. It’s basically like a pac-man, with a black star swallowing its accompanying neutron star in its entirety.”
“These are amazing events and we have waited a very long time to witness them. So it’s great to capture them in the end.”
One event included a black hole with a mass nine times that of our Sun and a neutron star with twice the mass of our Sun. The other event included a black hole with a mass about six times larger than our Sun and a neutron star with a mass 1.5 times.
Professor Scott, who is also principal investigator at the ARC Center for Excellence in Gravity Wave Detection (OzGrav), said the international team had previously captured many incidents that included two colliding black holes and also two colliding neutron stars.
“We have now completed the final part of the hut with the first verified observations of gravitational waves from a collision of a black star and a neutron star,” she said.
Dr. Johannes Eichholtz, of the ANU Center for Gravitational Astrophysics and a fellow researcher at OzGrav, said the two discoveries were originally made on January 5 and 15, 2020.
“Such revelations are very rare,” he said.
“We discovered these events not once but twice in ten days.”
“Like the ripples from these two events, which were felt a billion years later, these findings will have a major impact on our understanding of the universe for many years to come.”
To the scientific paper
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