Telescopes operated by National Aeronautics and Space Administration (NASA) recently observed a massive black hole devouring a star.
- The incident was the fifth-closest example of a black hole destroying a star and occurred 250 million light-years from the earth, in the centre of another galaxy.
- The astronomical phenomenon of the destruction of a star by a black hole is formally called a tidal disruption event (TDE).
What is a ‘tidal disruption event’?
- A tidal force is the difference in the strength of gravity between two points. If the tidal force exerted on a body is greater than the intermolecular force that keeps it together, the body will get disrupted.
- During a TDE, the tidal force of a black hole disrupts the star in vicinity. While about half of the star’s debris continues on its original path, the other half is attracted by the black hole’s gravitational pull.
- The gradual growth of this material bound to the black hole produces a short-lived flare of emission, known as a tidal disruption event.
- The event is formally called AT2021ehb and took place in a galaxy with a central black hole about 10 million times the mass of our sun.
- TDEs are attractive to astronomers because of their observability and short duration, and the opportunity to study the impact of black holes’ gravity on materials around them.