Tidal disruption event

Context: Recently telescopes operated by National Aeronautics and Space Administration (NASA) observed a tidal disruption event named AT2021ehb.

• This is the fifth-closest example of a black hole destroying a star occurred 250 million light-years from the earth, in the centre of another galaxy.
• It was first spotted in March 2021, by the Zwicky Transient Facility in Southern California.
• It took place in a galaxy with a central black hole about 10 million times the mass of our sun.

About Tidal Disruption Event (TDE):

• It is a phenomenon of the destruction of a star by a black hole.
• Gradual growth of this material bound to the black hole produces a short-lived flare of emission, known as a ‘Tidal disruption event’.
• Tidal force: It is a difference in the strength of gravity between two points.
  • If it is greater than the intermolecular force that keeps it together, the body will get disrupted.
• Tidal force of a black hole disrupts the star in vicinity.
• About half of the star’s debris continues on its original path, the other half is attracted by the black hole’s gravitational pull.
• TDE provides spectacular view of the corona’s formation and evaluation.

About NuSTAR Mission:

• The Nuclear Spectroscopic Telescope Array, or NuSTAR, mission studies the universe in high energy X-rays to better understand the dynamics of black holes, exploding stars and the most extreme active galaxies.
• In addition to complementing astrophysics missions studying the universe in various spectra, NuSTAR, the first hard-focusing X-ray telescope to orbit Earth, is expected to greatly improve on observations from ground-based observatories.
• NuSTAR science discoveries and highlights:
  • First measurement of black hole spin with high precision
  • Untangling the mystery of how stars explode
  • The discovery of a shockingly bright dead star
  • Staring deep into the hidden lairs of black holes
  • Contributed to the first picture of a black hole.

Source: The Hindu

Previous Year Question

Q.1) If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth? (2022)

1. GPS and navigation systems could fail.
2. Tsunamis could occur at equatorial regions.
3. Power grids could be damaged.
4. Intense auroras could occur over much of the Earth.
5. Forest fires could take place over much of the planet.
6. Orbits of the satellites could be disturbed.
7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.

Select the correct answer using the code given below:

1. 1, 2, 4 and 5 only
2. 2, 3, 5, 6 and 7 only
3. 1, 3, 4, 6 and 7 only
4. 1, 2, 3, 4, 5, 6 and 7