Black Hole

In News: Scientists from the Event Horizon Telescope (EHT) facility, revealed the first image of the black hole at the centre of the Milky Way.

• Astronomers believe nearly all galaxies, including our own, have these giant black holes at their centre
• The Milky Way black hole is called Sagittarius A*, near the border of Sagittarius and Scorpius constellations.
• It is 4 million times more massive than our sun.
• The image of Sagittarius A* (SgrA*) gave further support to the idea that the compact object at the centre of our galaxy is indeed a black hole, strengthening Einstein’s general theory of relativity.
• What is Black Hole?
  • Black hole refers to a point in space where matter is so compressed as to create a gravity field from which even light cannot escape.
  • Light gets chaotically bent and twisted around by gravity as it gets sucked into the abyss along with superheated gas and dust.
  • Black-holes were theorized by Albert Einstein in 1915.
  • A black hole has two parts:
  • Singularity at its core– a point that is infinitely dense, as all the remnant mass of the star is compressed into this point.
  • Event Horizon – There is a region of space beyond the black hole called the event horizon. This is a “point of no return”, beyond which it is impossible to escape the gravitational effects of the black hole.

  Event Horizon Telescope Project

  • EHT is a group of 8 radio telescopes located in different parts of the world.
  • In 2006, an international team of more than 200 researchers, led by Harvard University astronomers, launched the Event Horizon Telescope (EHT) project with a sole aim: to capture a direct shot of a black hole.

  General Theory of Relativity

  • Essentially, it’s a theory of gravity. The basic idea is that instead of being an invisible force that attracts objects to one another, gravity is a curving or warping of space. The more massive an object, the more it warps the space around it

Previous Year Questions (PYQs)

Q.1) Recently, scientists observed the merger of giant ‘blackholes’ billions of light-years away from the earth. What is the significance of this observation? (2019)

1. ‘Higgs boson particles’ were detected.
2. ‘Gravitational waves’ were detected.
3. Possibility of inter-galactic space travel through ‘wormhole’ was confirmed.
4. It enabled the scientists to understand to ‘singularity’.

Source: The Hindu & Indian Express