2023 APR 3
Geography > Cosmology > Cosmology
Why in news?
- Recently NASA confirmed that on October 9, 2022, our solar system was struck by a gamma-ray burst originating 1,900 light years away that was brighter than any since the beginning of human civilization, in what the space agency calls a "1 in 10,000 year" event that blinded space satellite sensors.
- It was named GRB 221009A.
About Gamma-Ray Burst:
- Gamma-Ray Bursts are the most powerful class of explosions in the universe, and they occur when massive stars die.
- When a massive star collapses, it creates a black hole, and the energy released during this process produces jets of high-energy particles that travel almost at the speed of light.
- These jets pierce through the collapsing star, producing X-rays and gamma rays, which can be detected by observatories on Earth and in space.
Types of GRBs:
- Long-duration gamma-ray bursts (LGRBs):
- LGRBs last for more than two seconds and are thought to be caused by the collapse of massive stars, known as supernovae.
- These explosions release a tremendous amount of energy and create a black hole at their center.
- LGRBs are the most common type of GRB and can be observed from distant galaxies.
- Short-duration gamma-ray bursts (SGRBs):
- SGRBs last for less than two seconds and are thought to be caused by the collision of two compact objects, such as neutron stars or a neutron star and a black hole.
- SGRBs are much rarer than LGRBs, are more difficult to observe and typically located closer to our galaxy.
About GRB 221009A:
- GRB 221009A was detected in October 2022, by NASA's Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, and Wind spacecraft.
- The signal originated from the direction of the constellation Sagitta, and it took approximately 1.9 billion years to reach Earth.
- The 5-minute-long radiation pulse was the brightest GRB ever and nearly 70 times brighter than any other such eruption ever observed.
- GRB 221009A provides astronomers with valuable insights into the formation of black holes and the mechanisms that produce gamma-ray bursts.
- The detection of GRB 221009A will help astronomers refine their understanding of the conditions required for the formation of black holes and the production of gamma-ray bursts
With reference to ‘Gamma-Ray Burst’, consider the following statements:
1. They are high-energy short gamma radiations which get released when massive stars collapse or die in the Universe
2. It doesn’t last for more than a second
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2