UPSC Express

What is a Black hole?

• A black hole is a celestial monster with gravitational field so intense no matter or light can escape.
• Black holes are extraordinarily dense entities formed when very massive stars collapse at the end of their life cycle.
• As black holes do not allow light to escape, it makes viewing them difficult.
• However, space telescopes with special tools can help find black holes.

About Event Horizon Telescope Project

• The Event Horizon Telescope (EHT) is a large telescope array consisting of a global network of radio telescopes and combining data from several very-long-baseline interferometry (VLBI) stations around the Earth.
• It’s a visionary international project to take the first photograph of a black hole.
• Aim: To observe the immediate environment of the supermassive black holes Sagittarius A* and Messier 87.
• Project: The scientists will be looking for a ring of light around a region of darkness representing the actual black hole. This is known as the black hole’s shadow or silhouette.

Supermassive Black Holes

• Supermassive black holes are the largest kind of Black holes, devouring matter and radiation and perhaps merging with other black holes.
• The researchers has targeted two supermassive black holes for the project:
  • Sagittarius A*: It is situated at the center of our own Milky Way galaxy, possessing 4 million times the mass of our sun and located 26,000 light years from Earth.
  • Messier 87: It resides at the center of the neighboring Virgo A galaxy, boasting a mass 3.5 billion times that of the sun and located 54 million light-years away from Earth.

Very Long Baseline Interferometry, or VLBI: In brief

• Very Long Baseline Interferometry, or VLBI, links together widely separated radio telescopes and allows astronomers to see the universe in more detail than ever.
• This is a very powerful technique in radio astronomy which is helpful in observing black holes, map the surfaces of stars, and even track the drift of continents right here at home.