Black holes spin in captivating embrace in stunning new simulation imagery

Binary black holes move in tandem before merging, scientists have found

Julia Musto
in New York
Friday 14 February 2025 19:00 GMT
Comments
Black holes spin in captivating embrace in stunning new simulation imagery

Binary black holes, systems consisting of two black holes in close orbit around each other, synchronize their spins before they merge together, according to new research.

The moment creates a beautiful sight in simulations of how space works.

In stellar clusters - groups of stars that can contain as few as a dozen to as many as millions - binary black holes can collide with massive stars. This collision can cause an explosion, disrupting or even destroying the star.

Black holes are astronomical objects with a gravitational pull so strong that not even light can escape them. They form when the core of a massive star collapses in on itself.

While it was commonly believed that the binary black holes formed in star clusters always have had random spins, scientists say that stellar collisions cause them to align their spins.

“When a massive star is torn apart by a binary black hole, it creates two separate streams of debris, each spiraling around one of the black holes,” explained Northwestern University’s Fulya Kıroğlu.

In stellar clusters, binary black holes can collide with massive stars. Now, new simulations show that these collisions influence the spins of black holes. As the black holes move closer together, their spins align with the binary orbit creating a beautiful sight in simuliations
In stellar clusters, binary black holes can collide with massive stars. Now, new simulations show that these collisions influence the spins of black holes. As the black holes move closer together, their spins align with the binary orbit creating a beautiful sight in simuliations (Jamie Lombardi/Allegheny College)

Kıroğlu a graduate student, led the research that has been accepted for publication in The Astrophysical Journal Letters.

“Initially, the direction of these spinning debris clouds is random. However, as the black holes get closer, powerful tidal forces begin to realign these clouds, gradually influencing the spin direction of the black holes themselves,” she explained.

Over time, Kıroğlu said that the process leads to black hole mergers with a “slight but consistent alignment of their spins.”

That’s something that had been seen in invisible ripples emanating from merging binary black holes detected by NASA’s LIGO/Virgo mission, but had not been fully understood until now.

Binary black holes are a system of black holes that orbit each other. A black hole is an astronomical object with a gravitational pull so strong that not even light can escape it.
Binary black holes are a system of black holes that orbit each other. A black hole is an astronomical object with a gravitational pull so strong that not even light can escape it. (Jamie Lombardi/Allegheny College)

New simulations show how the collisions influence the spins of black holes, ripping up the stars before eating the stellar debris and becoming more massive.

The additional mass increases their gravitational pull. ultimately realigning their spins in the same direction. Their spin looks like a “googly-eyed heart.”

“This discovery challenges the common belief that black holes formed in star clusters always have randomly distributed spins,” said Kıroğlu.

Join our commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in