The all encompassing death of a giant star collapsing in on itself, sucking in everything in its path including light and time, is a mind boggling thing to get your head around. That’s why black holes have captured human’s fascination ever since we discovered them in 1971. It is important for scientists to understand these matter sucking structures for wider knowledge of our universe, like details of its expansion.

A recent paper, published in The Astrophysical Journal, discusses how a group of scientists figured out exactly how many black holes there are in the universe. Like us, you may be wondering how this achievement is even possible. Black holes are difficult to spot anyway, with them lurking in pitch black environments while being black themselves.

Cleverly, astrophysicists from the International School of Advanced Studies (SISSA) in Italy, applied information we already know about star evolution. The group created a computer program including many aspects of the journey of a star, including; rate of formation, size, and elements they contain. Then, the model figured out which of these candidates could be transformed into black holes, as only extremely large stars develop into these. Other concepts such as the likelihood for the black holes to merge and how their distribution after this event would be impacted were also calculated.

With all of this considered, the group was able to estimate the number, distribution, and mass of the black hole population across the universe. The computer program predicted a whopping 40 quintillion (40,000,000,000,000,000,000) black holes populate the observable universe, making up around one percent of all matter.

From this study, researchers can get closer to the answers to other big questions. Such as concepts like the origins of black hole ‘seeds’ and consequently black holes.

Source study: The Astrophysical Journal – The Black Hole Mass Function Across Cosmic Times. I. Stellar Black Holes and Light Seed Distribution