c. Samsung / Niels War
In 2019, the LIGO/VIRGO collaboration took a gravitational wave signal from a black hole connection, which has proven to be one of the record books. Dubbed “GW190521”, it was the largest and most distant signal ever detected, and produced the strongest signal ever detected, more “pop” than the usual “drink”.
Moreover, the new black hole that formed as a result of the merger is about 150 times heavier than our sun, and GW190521 became the first direct observation of a black hole of medium mass. Even stranger, the two converging black holes were locked in an elliptical (not circular) orbit, and their spin axes were more inclined than normal compared to those orbits.
Physicists want nothing more than to present an interesting dilemma that does not immediately apply to the established theory, and GW190521 gave it to them. New theoretical simulations suggest that all of these peculiar features can be explained by the presence of the third individual black hole horn in the final dance of the binary system to create a “chaotic tango”. A new paper has been published in the journal Nature.
We mentioned earlier, on May 21, 2019, the inventors of the collaboration picked up the signal of a binary black hole connection: four short motions lasting less than a tenth of a second. The shorter the signal, the more black holes converge — in this case 85 and 66 solar masses, respectively. Together, the black holes formed a new, much larger black hole with a mass of about 142 solar masses, releasing energy equivalent to eight solar masses in the process – hence the strong signal the inventors took.
What made this event so extraordinary is that the 142 solar masses are located in the middle of what is known as the “mass gap” of black holes. Most of these objects fall into two groups: stellar mass black holes (ranging from a few solar masses to ten solar masses) and supermassive black holes, such as those in the middle of our Milky Way (hundreds to billions of solar masses). The former is the result of massive stars dying in a central collapse supernova, while the latter’s formation process remains a mystery.
LEGO/Caltech/MIT/R. Injury (IPAC)
It is unusual for a leading black hole to weigh 85 solar masses because it contradicts current stellar evolutionary models. The types of stars that form black holes between 65 and 135 solar masses do not become supernovae, and therefore do not end up as black holes. On the contrary, these stars will become unstable and reduce a significant part of their mass. Only then will they become supernovae – but the result will be a black hole less than 65 solar masses.