Scientists from the Hebrew University of Jerusalem’s Racah Institute of Physics have reconstructed the gruesome death of a star that ventured too close to a supermassive black hole. Using a sophisticated simulation, the team was able to retell the entire story of this event for the first time, shedding light on the unknown shock waves that occurred during the process. The findings, published in the journal Nature, not only explain the brightest periods of these star-destroying events but also provide valuable insights into the properties of supermassive black holes and the limitations of Einstein’s theory of general relativity.
Tidal disruption events (TDEs) occur when a star’s orbit brings it dangerously close to a supermassive black hole with a mass millions or billions of times greater than that of the sun. The immense gravitational forces generated by the black hole cause intense tidal forces within the star, leading to a phenomenon known as “spaghettification.” This process stretches the star vertically and squeezes it horizontally, transforming it into a thin strand of stellar plasma.
As the spaghettified plasma falls back towards the black hole, it encounters a series of shock waves that heat it up. This results in a highly luminous flare that can outshine all the stars in the surrounding galaxy for weeks or even months. The recent simulation by scientists Elad Steinberg and Nicholas Stone provides a comprehensive picture of TDEs, from the initial capture of the star by the black hole to the peak of the flare.
The simulation, made possible by pioneering radiation-hydrodynamics software developed by Steinberg, revealed a previously unknown type of shock wave that dissipates energy at a faster rate than previously believed. This discovery suggests that these shock waves and their associated energy dissipation power the brightest periods of TDEs.
The implications of these findings are significant. Astronomers can now use TDEs to gain insights into the properties of supermassive black holes, such as their mass and rate of spin. Additionally, studying the mechanics of these powerful shock waves through real-world observations of black hole-star encounters can further our understanding of these cosmic events.
The reconstruction of this cosmic crime scene marks a milestone in our exploration of the universe’s most violent encounters. By unraveling the mysteries of TDEs, scientists are not only uncovering the fate of stars unfortunate enough to wander too close to black holes but also gaining valuable knowledge about the fundamental forces that govern our universe.
