Supermassive black holes provide the necessary material to the newly formed black holes to grow and expand.

Black holes have always been an intriguing phenomenon since its discovery. Researchers from different parts of the world make considerable investments of time and money to understand these amazing marvels of nature. This led to a lot of outstanding information about the black holes including a violent collision between the two of them, which took place last year. Scientists continued their research work in order to figure out how these smaller black holes grow before merging into each other and they have finally found something in this regard which is simply astonishing.

According to the latest research, the size of an average black hole can increase by eating up the circling material around the supermassive black hole of the galaxy. It offers a completely new explanation to the world because most of the prior theories were focused on a low-metal diet of the stars. This may also offer a new source of gravitational waves to the humanity. Previously, it was believed that the black holes are actually those giant stars who had very few metals in the early days of their lives. The stars who have lower concentrations of metal in them usually generate weaker solar winds which help them to keep most of their mass intact before collapsing into a black hole.

Researchers became curious about the size of the baby black holes when they detected 6 different signals of the gravitational waves, recently. It was observed that 5 of them came from merging pairs of stellar-mass black holes while a pair of neutron stars merged to produce the last signal. In the past, a number of studies have proven that the mass of a stellar-mass black hole is about 10-15 times the mass of our sun at the time of its formation. Contrary to that, most of the black holes observed in this research were more than 20 times bigger than the Sun. This variation offered sufficient room for the scientists to explore and they did just that.

It is a common information that most of the large galaxies have supermassive black holes in their cores. Majority of them remain quite passive for most of their lives. They accrete a negligible quantity of matter due to which minimal light is generated by them. On the other hand, some of these supermassive black holes are engulfed by a dense disk of dust and gas which spins towards the center of these holes. Due to the immense grinding of disk materials, a bright glow is observed from these black holes. The disks that are incredibly bright are called the Active Galactic Nuclei (AGN).

The latest findings reveal that it is very much possible for a couple of nearby stellar-mass black holes to become trapped within these AGN disks. This allows the black holes to gather all the available material and grow considerably during this phase. The mass of such black holes, at the time of the merger, is somewhere around the 20 solar masses mark. It is an interesting development because the size of these baby black holes is much smaller in the first place.

The researchers mentioned that the environment of these black holes is quite conducive for synchronizing the axes of their spinning motion. This means that both these stellar-mass black holes are moving in tandem before merging into each other. According to an estimate, this kind of systems releases 10% of their total energy in the form of gravitational waves while randomly oriented systems convert only 3% of their energy into gravitational-wave energy. As a result, the detection of these systems is possible with the Laser Interferometer Gravitational-wave Observatory (LIGO), one of the most advanced technologies of current times.

In addition to these gravitational waves, these black holes emit a substantial quantity of Gamma rays, X-rays, and Radio waves, which have a lot of precious information for the scientists to decode. Such an incident was observed last year during a merger between two neutron stars. Josh Simon, an Astronomer at the Carnegie Observatories talked about that in the following words:

“There are things you can discover with gravitational waves that you could never see with electromagnetic light, and vice versa. Having that combination should provide us with insights into these extreme objects.”