BLACK HOLES

BLACK HOLES

TOPIC: Science & Tech

Context- The supermassive black hole at the centre of the Milky Way, which has a mass 4 million times greater than the Sun, is observed.

Concept-

• Observations showing a roughly dough-nut-shaped cloud of cosmic dust and gas shrouding a supermassive black hole at the centre of galaxy Messier 77 similar in size to our Milky Way.

About Black Holes:

• Black holes are extraordinarily dense objects possessing gravitational pulls so powerful even light cannot escape them.
• It refers to a point in space where the matter is so compressed as to create a gravity field from which even light cannot escape.
• The concept was theorized by Albert Einstein in 1915 and the term ‘black hole’ was coined in the mid-1960s by American physicist John Archibald Wheeler.
• The black holes belong to two categories:
  • One category ranges between a few solar masses and tens of solar masses. These are thought to form when massive stars die.
  • The other category is of supermassive black holes. These range from hundreds of thousands to billions of times that of the sun from the Solar system to which Earth belongs.

Messier 77:

• Messier 77, also called NGC 1068 or the Squid Galaxy, is located 47 million light years – the distance light travels in a year, 9.5 trillion km – from the Earth in the constellation Cetus.
• Its supermassive black hole has a mass roughly 10 million times greater than our sun.