Monster black hole discovered after scientists observe two smaller black holes colliding 7 billion years ago

The two so-called GW190521 black holes merged to form the new massive black hole, the first time such large black holes have been observed either by gravity or by electromagnetic observations. Mark Myers, ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav)

The creation of a massive black hole, with a mass 142 times greater than the Sun, has been detected after two medium-sized black holes collided 7 billion years ago.

The largest known black hole collision was recorded while an international consortium of astronomers, including 16 from the Warsaw University Observatory and National Centre for Nuclear Research, were examining gravitational waves and detected four short wiggles passing through the Earth.

Scientists picked up four short wiggles passing through the earth.Raul Rubio/ Virgo Valencia Group/ The Virgo Collaboration

The source of the signals was traced back to the seven-billion-year-old collision, over ten billion light-years away.

The two so-called GW190521 black holes, one 66 times the mass of the Sun, the other 85 times the mass, merged to form the new monster black hole, the first time such large black holes have been observed either by gravity or by electromagnetic observations.

The source of the signals was traced back to the seven-billion-year-old collision, over ten billion light-years away.Raul Rubio/ Virgo Valencia Group/ The Virgo Collaboration

Professor Dorota Rosińska, a member of the Polish Virgo-Polgraw team, said: “The discovery of GW190521 is undoubtedly a major challenge for contemporary astrophysics, cosmology and fundamental physics.

“For the first time, we have observed the coalescence of two black holes of such unusual masses and the creation of a medium-mass black hole.

“It was the most energetic and the most distant event from Earth, which was recorded in gravitational waves.

“With the increasing sensitivity of the detectors, we will observe more and more phenomena from the early Universe.”


The gravitational wave that led to the discovery was registered on May 21st, 2019 by three detectors. The signal, which lasted only 0.1 seconds, was then examined by scientists, who estimated the distance to its source at about 17 billion light years.

The discovery of GW190521 confirms the existence of “black holes of intermediate-mass” ranging from 100 to 100,000 times the masses of the Sun.

The discovery of GW190521 confirms the existence of “black holes of intermediate-mass” ranging from 100 to 100,000 times the masses of the Sun.Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut)/YouTube

Interest in this population of black holes is connected with one of the most fascinating and difficult puzzles facing astrophysicists and cosmologists: the origin of supermassive black holes.

These gigantic monsters, millions, and even billions of times heavier than the Sun, usually located in the centres of galaxies, can be created by merging smaller black holes of intermediate-mass.

Professor Dorota Rosińska, a member of the Polish Virgo-Polgraw team, said: “The discovery of GW190521 is undoubtedly a major challenge for contemporary astrophysics, cosmology and fundamental physics.”Marcin Obara/PAP

Scientists expect, that with the method they now employ, they will be able to identify more of such middle-weight black holes.

The Virgo project combines the works of about 580 scientists, engineers, and technicians from 109 institutes in 13 countries, mainly European: Belgium, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Monaco, Portugal, the Netherlands, Portugal, Spain, and Poland.

The monster black hole is the largest ever recorded.Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut)/YouTube

The American equivalent is the LIGO project, which has two detectors in the USA. Institutes from outside the United States also participate in the project.

In total, about 1300 scientists from all over the world work within the LIGO consortium. LIGO and Virgo work closely together.