UPSC Articles
Active Galactic Nuclei
Part of: Prelims and GS-III Space
Context: A roughly dough-nut-shaped cloud of cosmic dust and gas covering a huge black hole at the center of a galaxy Messier 77, which is similar in size to the Milky Way, was recently observed.
- The observation is providing scientists with new clarity about the universe’s most energetic objects.
Key takeaways
- Their recent observations lend support to predictions made three decades ago about “active galactic nuclei”.
- It also provided strong support for the “unified model” of active galactic nuclei.
- This model holds that all active galactic nuclei are basically the same but that some have different properties.
Active galactic nuclei
- These are places at the centres of many large galaxies that have tremendous luminosity which sometimes outshine all of a galaxy’s billions of stars combined and produce the universe’s most energetic outbursts.
- The energy arises from gas violently falling into a supermassive black hole that is surrounded by a cloud of tiny particles of rock and soot along with mostly hydrogen gas.
Black holes
- Black holes are extraordinarily dense objects possessing gravitational pulls so powerful even light cannot escape them.
- Supermassive black holes, which reside at the centre of many galaxies, including Milky Way, are the largest of them.
Messier 77
- Messier 77, also called NGC 1068 or the Squid Galaxy, is located 47 million light years (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.
News Source: TH
