At present, the universe continues to be an enigma for all human beings. It's not just about stars and planets, it goes beyond the human eye. Discover here what are quasars or quasars? Impressive elements of the universe that you surely did not know
What are quasars?
The quasars o quasar They are celestial bodies, whose nucleus presents a brightness of great intensity. These formations are millions of kilometers away from planet Earth and although they seem Starsthey really aren't.
Scientists believe their formation is due to the contribution of large amounts of gas falling into the black holes present in galaxies. For more information about these enigmatic objects, you can consult the link to supermassive black holes.
Perhaps they represent the initial process of transformation of galaxies. As a result of the constant energy exchanges in gravity, quasars turn into heat energy and radiation.
Thanks to the constant transformation and release of energy, a disk or radius of great magnitude is generated, charged with an electromagnetic force, capable of producing a high-intensity glow.
If you want to observe quasars with not very advanced telescopes, it will be quite difficult for you. Due to their distance from Earth, even when viewed with different types of high-powered telescopes, they will appear as small luminous points in the sky.
The discovery of these celestial formations
It was the 30s, when Karl Jansky, who was an engineer attached to the Bell Telephone company laboratory, was investigating the causes of interference in long-distance telephone communications.
His research consisted of making recordings, through a satellite dish that he built himself. After making records for several months, he was able to identify static coming from: thunderstorms that were near, far away, and a repeat of continuous whistles, which he was unable to identify.
After analyzing the phenomena he had recorded using scientific criteria, he was able to determine that the static distortions occurring on the telephone lines were caused by signals originating from the Milky Way.
Once the war between the most powerful powers ends, a fact that was described as World War II. There was an accelerated development of Radio Astronomy and scientists were able to identify the origin of the radio signals that came from the galaxy.
The work begun by Karl Jansky is continued by another American engineer, Grote Reber. But to delve deeper into the investigation, he designed his own version of a radio telescope and managed to determine that the waves they captured were the product of the radiation generated by black bodies.
The assertion of black bodies made by Reber, kept scientists in constant investigations. As a result of the studies, Vitaly Ginzburg in 1950 developed a theory to explain the radio waves of the Milky Way.
Also in the 1950s, Martin Ryle built the first Interferometer, with which they could visualize the separation of radio waves. With which he was able to pave the way for further investigations of quasars.
During observations made by scientists in 1962, while collecting data on radio emissions from a celestial object, the Moon came between the observation base and the point of emission.
During the occultation event, thanks to the Radio Telescope, which is part of the family of types of telescopes, which astronomers used, were able to identify a very small star. This star emitted blue electromagnetic waves, in addition to emanating radio waves.
Quasar characteristics
- They are objects of great luminosity, which can easily exceed the light emitted by a group of galaxies.
- Quasars have a highly variable luminosity. Being able to change in a matter of days, which helps in the precision of the calculation of its radiation core.
- They are capable of emitting large amounts of ultraviolet radiation, X-rays, among other types of electromagnetic radiation.
- Due to the power of their radio emanations, they can be seen at a distance greater than 10.000 million light years.
- They are fed with the energy released from the different rearrangement processes of the galaxies.
- They form in the nucleus of new galaxies and then transform into a very bright celestial body.
- The gases that surround the quasar can reach extremely high temperatures.
- Inside these celestial objects enormous movements of friction and states of extreme agitation are produced.
- They reach high levels of radiation.
Quasars and the Third Cambridge Catalog
The third Cambridge Catalog is like a type of astronomical list where the celestial bodies whose radio waves were detected in a range between 159 and 178 Megahertz were recorded.
This catalog was published in the late 1950s by what were then the members of the Cambridge University radio astronomy team.
The scientists of the radio astronomy team agreed to use the following nomenclature:
- The 3C prefix alludes to catalog number three and would be seconded by the number of records or entries made in the list. All the records that were recorded in it were made with the help of the Cambridge University Interferometer.
Observations made at the 178 Megahertz frequency by John Caister Bennett in the early 60s led to some adjustments to the catalogue.
Of the adjustments made to the Cambridge catalog, the following appear:
- The band of radio waves accepted as definitive is that of 178 MHZ.
- Excluded from the list are all those bodies whose flow is less than 9 Jansky or Jy.
- In order not to cause repetitions in the records of celestial observations, other sources were included for the record, which included the use of decimals.
Due to technological limitations in the 60s, in 1983 astronomers Julia Riley and Malcolm Longair set out to make another revision of the Cambridge catalogue.
These scholars of the stars affirmed that they had been excluded from the list, galaxies that also met the patterns of their flow and declination limits. However, due to technological deficiencies in the observation equipment, they were left out.
Cambridge Catalog Object 273
The Cambridge Catalog is a list of astronomical objects where the radio sources of the celestial bodies that were initially detected were recorded.
A radio source was identified in the early 60s, under the supervision of astronomer Cyril Hazard. This astronomy scholar detected a radio source that he cataloged as 3C273.
The nomenclature Hazard used to identify object 3C273 was because it corresponded to discovery number 273 and would be included in the third Cambridge catalogue.
This stellar object was related to the constellation of Virgo, located at a distance of several million light years. Thus becoming the celestial object that was furthest away in the universe.
Quasars cause the disappearance of galaxies
Since the very discovery of quasars, astronomers believed that when galaxies reached this stage, they stopped producing new stars. But all that theory ceases to have effect, with the discovery of Allison Kirkpatrick.
This researcher from the University of Kansas, together with a select group of scientists, discovered the state of lethargy that the galaxy can enter, even with the presence of quasars in its nucleus.
Currently, the scientific community believed that with the appearance of quasars in the center of galaxies, all the gases and other materials present were dragged by this black hole. And expelled to form other stars.
But the group led by Kirkpatrick observed that a phase of torpor or transition took place within the galaxy, once the quasar had formed. Without totally losing its stellar conformation, immediately.
cold quasars
This is a rare type of galaxy, the discovery of which completely changed the perception of what the end of its life cycle was like. Like other quasars, cold quasars originate from a black hole surrounded by cosmic gas and dust.
The presence of large amounts of gases and due to the effect of the fusion of their nucleus, they become super bright objects. The gas and dust that falls into the inner part of the quasars are expelled into space.
The previous observations of the quasars, referred that the galaxy when it was already near its end, also entered a state of passivity. And it lost the ability to produce new stars.
But Kirkpatrick's team found that a small portion of the cool quasars remained in the process of forming new stars.
After his intense observations made by the researcher Kirkpatrick and with his postulate of the existence of a phase of passivity, before the galaxy completely extinguished. A question arises:
Is our galaxy at risk of the same end, from cold quasars?
Theoretically, yes, the galaxy could have that same fate. But according to projections made by researchers, this would happen in approximately 4 billion years.
There is still a long way to go before they can accurately state everything that could happen to our planet Earth, once the collapse of the galaxies occurs.
Which quasar is the most distant?
A group of international scientists managed to discover the quasar that is the most distant from observation posts on Earth.
The celestial object was named ULAS J and is about 13 billion light-years distant from Earth. The researchers estimated that the mass of the black hole present in the quasar is 2 billion times that of the Sun.
It could be seen by the research team, thanks to the observation equipment available to the European Southern Observatory THAT. Although much more distant objects have been seen, ULAS J1120 has a greater intensity in its brightness.
The particularity of this recently located quasar is that thanks to its luminosity, it behaves like a great cosmic lighthouse that is capable of illuminating the areas near it without any problem.
Black holes
It is said that the black hole is a formation that occurs in an area of the Universe and that from it, nothing that enters can leave. Due to the absorption that is generated inside its core.
If it were the case that its mass is extremely large, then its gravity would increase in the same proportion, causing the attraction of all its matter.
Once it has become self-attracted, it continues to absorb whatever comes near its core. Its power of absorption is so powerful that it is capable of trapping and encapsulating light. The core of the hole is nourished by everything that falls into it and causes an increase in mass and gravity.
Training
The process of extinction of large stars, originate the formation of black holes. Due to the high temperatures present in an active star, an enlargement of the star occurs, balancing its gravity with this.
But this effect is reversed, once the core cools down. That is, the star contracts.
When do we know if we are in the presence of a black hole?
They are quite difficult to observe due to their poor or nonexistent visibility. This is because any light that may be present near them is absorbed. The only way to detect their presence is through the effect of gravity on their surroundings:
- The bodies that are affected by its gravity, suffer a change in their usual movement.
- Its presence can also be predicted by X-rays, which are emitted when its matter, due to the same effect of attraction, is increased.
Characteristics of black holes
Some of the most relevant characteristics of these celestial objects are mentioned below:
- Enormous power of gravitational attraction. So strong that not even light is able to escape from it.
- The mass is much larger than that of the Sun.
- They do not have a solid surface.
- The emission of its radiation is also known as Hawking radiation.
- Externally, they have no distinctive features. They only have mass, charge, and angular momentum.
- They can be located in the central part of galaxies.
PREMIUM QUALITY
Currently, scientists have managed to determine the existence of three types of black holes:
- Stellar: they are black holes, which originated from the disappearance of massive stars.
- Super massive: they are characterized by having masses greater than that of the Sun, by 10.000 million times.
- Primordial: are those holes that originated from the growth of the Universe.
parts of a black hole
- event horizon.
- ergosphere.
- ISCO or Innermost Stable Circular Orbit.
- accretion disk.
- Jets or jets.
