What are Quasars?

About Quasars: 

• The quasi-stellar radio sources (Quasars) were first discovered six decades ago.
• These are very luminous objects in faraway galaxies that emit jets at radio frequencies.
• They are located in supermassive black holes, which sit in the centre of galaxies.
• These are formed by the energy emitted by materials spiralling around a black hole right before being sucked into it.  
• Most quasars are larger than our solar system. A quasar is approximately 1-kilo parsec in width.
• When galaxies collide, it pushes the gas from the outer reaches of the galaxies to the centre.
• As the supermassive black hole gorges on the gas, it releases ferocious fountains of energy in the form of radiation, leading to the quasar.

What is a Blackhole?

• A black hole is an area in space with extremely intense gravity from which even light cannot escape. 
• A black hole can be formed by the death of a massive star.
• Examples of a black hole are Cygnus X-1 and Sagittarius A* etc.

 

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Q1) What is Gravity?

Gravity is a fundamental force in the universe that attracts all matter towards each other. It is what keeps the planets in our solar system orbiting around the sun and what causes objects to fall to the ground when dropped.

Source: Galaxy mergers ignite ‘quasars’ — the most powerful celestial objects: Study