Quasar

Why in News?

Recently, the astronomers have identified a remarkable water reservoir circling a quasar over 12 billion light-years away.

• Quasar – It is a subclass of Active Galactic Nuclei (AGNs), extremely luminous galactic cores where gas and dust falling into a supermassive black hole.
• Formation – It occur when immense amounts of matter fall into a supermassive black hole, spiraling around it in the form of a disk before entering.
• Luminous object – The accretion disk is subjected to extreme gravitational and frictional forces, causing the gas and dust to heat up to millions of degrees.
• Thus, it become luminous, blasting out dazzling jets of material into the universe.
• Together, the jets and glowing disk outshine their host galaxies.
• Features – Though they aren’t much bigger than Earth's solar system, they emit 100 to 1,000 times as much light as an entire galaxy.

• Discovery – They were 1^st found in the 1950s and 60s and labeled “quasi-stellar radio sources,” because they looked like stars but emitted radio waves.
• The closest quasars to Earth are 100s of millions of light-years away.

Hubble telescope found quasars in both spiral and elliptical galaxies, colliding and undisturbed, which may indicate a subtler mechanism for feeding a supermassive black hole than galaxy collision.

Quasar APM 08279 5255

• Size - It surrounds a supermassive black hole that is 20 billion times more massive than our Sun.
• Energy – It pumps out as much energy as a 1000 trillion suns.
• Water reservoir – It contains water vapour equating to 140 trillion times the volume of Earth’s oceans.
• It is the farthest and largest known reservoir of water source in the universe.
• Features – It is emitting hydrogen-rich gases like water vapour and carbon monoxide, and creating a region 100s of light-years wide.
• The gas is warm and dense compared to typical galactic conditions.
• The intense radiation from the quasar keeps the surrounding gas active.
• It primed for star formation or feeding the black hole, potentially increasing its mass 6 fold.

References

1. Telangana Today| Water Reservoir Surround a Quasar
2. ESA| Quasar