The formation of quasars
Although scientists discovered quasars about sixty years ago, they did not know anything about its exact origin; But recently they revealed this mystery. They reached answers by observing 48 different galaxies including quasars and comparing them with 100 galaxies without quasars.
According to new findings, the collision of galaxies is the cause of the formation of quasars. As two galaxies merge, a large amount of gas is transported towards the supermassive black hole at their center. Before the gases become food for the black hole, a large amount of energy is released in the form of jets of radiation, creating quasars.
Many large galaxies host supermassive black holes at the center as well as large amounts of gas, but this gas is usually out of reach of the starving central black hole. As the galaxies collide, all of this gas is funneled toward the black hole, producing enough rays and radiation to power a bright quasar.
The formation of a quasar can absorb a galaxy’s remaining gas, depriving it of essential star-forming material, sometimes for billions of years.
Types of quasars
Just like black holes, quasars are of different types and can be classified into different groups, including loud radio quasars, quiet radio quasars, broad absorption line (BAL) quasars, type 2 quasars, red quasars, and optically variable quasars (OVV). and weak beam line quasars.
Quasars and Blazers
Both quasars and blazars are active galactic nuclei known for their high brightness. The main difference between quasars and blazars is the angle of their relativistic jet. The angle of the quasar has a slight deviation with respect to the Earth, while the blazar is perfectly aligned with the Earth. Blasers are divided into two categories: BL Lac objects and quasars (OVVs).
Discovery and observation of quasars
The first quasars (3C 48 and 3C 273) were discovered in the late 1950s in the survey of radio sources in the sky. Initially, these objects were known as radio sources without visible mass. By the 1960s, hundreds of quasars were recorded and published in the third Cambridge Catalog. In 1963, a precise identification of the radio source 3C 48 with an optical mass was published by Alan Sandage and Thomas E. Matthews. These astronomers identified a blue-looking star at the location of the radio source and by examining its spectrum, they noticed its unknown radiation lines.
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