Quasars

In News

• The collision of two galaxies likely ignites quasars, the new study published in journal Monthly Notices of the Royal Astronomical Society highlighted.
  • The collisions were discovered when researchers, using deep imaging observations from the Isaac Newton Telescope in La Palma.

What are Quasars?

• A quasar (also known as a QSO or quasi-stellar object) is an extremely luminous active galactic nucleus (AGN). 
• Quasars were first discovered six decades ago. They are located in supermassive black holes, which sit in the centre of galaxies.
• As a supermassive black hole feeds on gas and dust, it releases extraordinary amounts of energy in the form of radiation, resulting in a quasar.
  • Black hole is a point in space where matter is so compressed as to create a gravity field from which even light cannot escape.

What does the study say about Quasars?

• Quasars are a consequence of galaxies crashing together: Most galaxies have supermassive black holes at their centers. They also contain substantial amounts of gas—but most of the time this gas is orbiting at large distances from the galaxy centers, out of reach of the black holes. 
  • Collisions between galaxies drive the gas towards the black hole at the galaxy center; just before the gas is consumed by the black hole, it releases extraordinary amounts of energy in the form of radiation, resulting in the characteristic quasar brilliance.
• Future Prospects of Galaxies: The ignition of a quasar can have dramatic consequences for entire galaxies—it can drive the rest of the gas out of the galaxy, which prevents it from forming new stars for billions of years into the future.
  • It is likely to represent the future of our own Milky Way galaxy when it collides with the Andromeda galaxy in about five billion years.

Significance of quasars

• Quasars play a key role in our understanding of the history of the universe, and possibly also the future of the Milky Way.
• Quasars act as “cosmic lighthouses”, allowing researchers to see the outer reaches of the universe.
• NASA’s James Webb Space Telescope will study the earliest galaxies in the universe. The telescope is capable of detecting light from even the most distant quasars, emitted nearly 13 billion years ago.

Source: DTE