Turbulent spacetime and destroyed stars show how fast supermassive black holes spin

Main) an illustration of a black hole ripping apart a star in a tidal disruption event (Inset) an image of a spinning black hole dragging spacetime along with it (Image credit: ESA/C. Carreau/ Robert Lea (created with Canva))

“Frame dragging is an effect that occurs in all rotating black holes.” The “wobbly” remains of a star that died a horrible death in the mouth of a supermassive black hole are helping to reveal the cosmic predator’s rotation speed. Trending Next full moon Best telescopes Best binoculars Best star projectors Space calendar LEGO Star Wars sale Best dronesPlanets in the solar system Tonight’s night sky When you buy through links on our site, we may earn an affiliate commission. Here’s how it works. Black holes Turbulent spacetime and destroyed stars show how fast supermassive black holes spin News By Robert Lee, published 21 hours ago “Frame dragging is an effect that occurs in all rotating black holes.” (0) In the background, we see a bright pink accretion disk swirling around the black hole singularity. A trail of orange material retreats. The inset at the top right shows a diagram of a rotating black circle. Main page) Illustration of a black hole tearing apart a star during tidal disruption (inset) Image of a spinning black hole dragging it through space-time (Image credit: ESA/C. Carreau/Robert Lea (created with Canva)) The “wobbly” remains of a star that died a gruesome death in the mouth of a supermassive black hole are helping to reveal the speed of rotation of a cosmic predator. advertisement Supermassive black holes are thought to be formed by successive mergers of smaller black holes, each providing angular momentum that accelerates the rotation of the resulting black hole. As a result, measuring the rotation of a supermassive black hole could provide insight into its history, and a new study suggests that such conclusions could be drawn based on the effects of a black hole’s rotation on the structure of space-time. We offer a new way to derive The doomed star at the center of this study was brutally torn apart by a supermassive black hole during a so-called tidal disruption event (TDE). These phenomena are caused when a star gets too close to the massive gravitational influence of a black hole. When a star gets close enough, huge tidal forces develop inside the star, compressing it horizontally and expanding it vertically. This is called “spaghettiization” and is the process of turning stars into bundles of star noodles. But importantly, not all of them will be swallowed up by a destructive black hole.

Some of this material is blown away, while some of it wraps around the black hole, forming a flattened cloud called an accretion disk. Not only does this accretion disk gradually feed the central black hole, but the same tidal forces that shredded the star in the first place also cause massive friction forces that heat this platter of gas and dust, causing it to glow brightly. 

source: https://www.nature.com/articles/s41586-024-07433-w