They are compact, incredibly bright and still hide a huge amount of secrets. Quasars! It is extremely difficult to understand exactly what we are dealing with because of its unusual nature. What do quasars represent and why do they attract attention?
The word itself is an abbreviation for “quasi-stellar”, that is, a “star-like object”. The phenomenon began to be discussed back in the 1950s. Astronomers began to notice in the galaxies a small number of anomalous objects, whose properties could not be explained by standard laws of physics.
The structure of the quasar
These mysterious sources released a huge number of rays in different frequencies. But in the optical observation they saw only a weak point glow. Therefore, there was a prejudice that we have far stars.
In the late 1950s. managed to find the first two quasars 3C48 and 3C273. Further analyzes showed that their spectral lines showed a remarkable red shift, which indicated a great distance from us. To date, we have managed to find more than 200,000 quasars. It is believed that they are much more.
Quasar 3C 273 in the constellation Virgo
It is important to understand that this is one of the brightest sources in the Universe, surpassing the brightness of the flash of supernovae. They are so bright that they overshadow the glow of the stars of a whole galaxy or even a few. For comparison, the average quasar creates 10 trillion. times more energy per second than solar indicators. However, this is not the limit! In 2019, the quasar J043947.08 + 163415.7 was found, which is 12.8 billion light-years distant from us. It is considered the brightest quasar today with a brightness of 600 trillion. sunny!
A quasar at a distance of 12.5 billion light-years shines near a young galaxy (12 billion light-years). ALMA instruments caught ionized carbon (green) and a star-shaped disk (blue)
What is it? A group of stars, an object or just a phenomenon? Modern theory says that a quasar is an active supermassive black hole in the galactic center. By activity is meant the process of nutrition. The giant black hole draws in the surrounding matter, creating an accretion disk. Charged particles in the disk accelerate, collide and release strong light rays. But the brightness increases even more if the black hole has a powerful magnetic field.
So we can say that quasars are not an object, but rather a complex structure of several elements, whose interaction allows you to create some of the brightest sources in outer space. Since quasars can be observed at large distances, they are called beacons of the Universe and are used to study the evolution and structure of outer space.
Interesting facts about quasars
- Quasars belong to the group of active galactic nuclei and are considered the most distant and energetic objects.
- Quasars are able to exceed the Milky Way 100 times in brightness.
- Their brightness allows them to eclipse all the stars in their home galaxy.
- They are considered the most distant objects in the entire history of observation. The farthest quasar found is 29 billion light-years distant from us.
- Quasars can only be found using radio telescopes, since they appear to be standard stars in the optical survey.
- Charged particles in an accretion disk of a quasar rise when moving upwards and, due to the twisted magnetic field lines, form a dense pillar - quasar jets.
- Charged particles inside quasar jets move almost at the speed of light.
- Quasars are moving away from us at tremendous speeds. Some accelerate to 93% of the speed of light! For example, the indicator 3C196 is 200 000 km / s.
- It was possible that there used to be a quasar in the Milky Way galaxy, but he died. However, a new one may appear when the Milky Way collides with the Andromeda Galaxy.