Astronomers using the European Southern Observatory's (ESO) Very Large Telescope (VLT) recently discovered the quasar, called P172+18, which is so far away that it takes about 13 billion years for the light from this quasar to reach Earth
Context
Astronomers using the European Southern Observatory's (ESO) Very Large Telescope (VLT) recently discovered the quasar, called P172+18, which is so far away that it takes about 13 billion years for the light from this quasar to reach Earth
What are the key-findings?
- The newly discovered quasar is called P172+18.
- It was found in a sky survey using optical light, and had colors that indicated it was at great distance.
- A follow-up observation confirmed its great distance: About 13 billion light years (or, more accurately, it took 13 billion years for the light to reach us).
- The distant, jet-shooting quasar is powered by a supermassive black hole that's about 300 million times more massive than Sun and is growing quickly, pulling in and swallowing surrounding matter with its gravity.
- While the new find is not the most distant quasarever detected, it appears to be the most distant radio-loud quasar, or radio jet-emitting quasar.
Quasar
- The word quasar is short for "quasi-stellar radio source".
- Quasar is a type of active galactic nucleus.
- In addition to radio waves and visible light, quasars also emit ultraviolet rays, infrared waves, X-rays, and gamma-rays and are brightest objects in the universe
- They are thought to be powered by super massive black holes which lie at the center of massive galaxies.
- However, the black holes themselves do not emit visible or radio light (i.e. they are “black”) – the light we see from quasars comes from a disk of gas and stars called an accretion disk, which surrounds the black hole.
- Quasar emission can only last as long as there is fuel available to form an accretion disk.
- Quasars can consume up to 1000-2000 solar masses of material per year, and have typical lifetimes of around 100-1000 million years. Once they have exhausted their fuel supply, the quasar will “turn off”, leaving the much fainter host galaxy.
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