What Are Quasars?

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Quasars

A Quasi-stellar radio source, also known as a quasar, is an extremely distant nucleus to an active galaxy. They are the furthest objects away from our galaxy that can be seen, but are visible to us because they are the brightest matter in our universe. Quasars are known to have an extremely high redshift. Though we have not been observing quasars for long enough to determine how they are born, they are believed to have been formed by supermassive black holes consuming an enormous amount of matter. This matter forms an accretion disc around the black hole, forming an area in which the matter can no longer escape the black hole. An accretion disk is a flat, disk-like structure of gas and debris that rapidly spirals around a larger object, like a black hole, a new star, a white dwarf, etc. It is similar to water swirling around in a sink around the drain. A quasar gradually attracts this gas and sometimes other stars or even small galaxies with their super strong gravity. These objects get sucked into the black hole. When a galaxy, star or gas is absorbed into a quasar in such a way, the result is a massive collision of matter that causes a gigantic explosive output of radiation energy and light. This great burst of energy results in a flare, which is a distinct characteristic of quasars. The movement of debris in the accretion disc, especially as it nears the black hole, causes it to be violently torn up, releasing electromagnetic radiation. This emits radio waves and x-rays, which travel to us as light. The death of a quasar has also not yet been proven, for similar reasons. One theory is that as more matter is sucked in, the radiation emission becomes less efficient. This would cause a decrease in light emission, which would cause the quasar to lose brightness, radioactivity, and therefore the accretion disc could deteriorate, causing the quasar to lose its defining characteristics. A quasar’s death can be described, like the accretion disc and black...
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