Astronomers have discovered the remotest blazar in history
PSO J030947.49 + 271757.31 is the catalog designation of the most distant blazar that has been observed so far. The light that is currently reaching us from him was emitted when the universe was less than a billion years old, or some 13 billion years ago.
Although from the very beginning the discoverers of the PSO J0309 + 27 blazar suspected that it was a distant object, and the X-ray observations with the Swift Space Telescope confirmed that it was a blazar, it was only the observations made with the spectrograph installed on the Large Binocular Telescope (LBT) ) confirmed a record distance to this object. This is the furthest known blazar.
Blazer, but blazar?
Blazars are one of the brightest objects belonging to the group of active galactic nuclei (AGN) or supermassive black holes located in the centers of galaxies. Their activity causes the presence of a disk or sphere of ionized gas that drive the emission of radiation in many wavelength ranges. Blazars emit extremely strong relativistic jets, bright enough to be seen from distant places in the universe. The jets emitted by blazars are visible only along the line of sight. If the Earth is not in this line, they are extremely difficult to see.
In this case, however, the blazar observed by scientists is one of the earliest, most distant supermassive black holes not covered by large amounts of dust (unlike most AGNs). Thanks to this, scientists are able to study it in the entire electromagnetic spectrum.
The spectrum that appeared to our eyes confirmed that PSO J0309 + 27 is indeed AGN - a galaxy whose core is extremely bright due to the presence of a supermassive black hole devouring huge amounts of gas and stars. What's more, data obtained using LBT confirmed that blazar is really far away from us - says Silvia Belladitta, a PhD student at the University of Insubria and the author of a scientific article that appeared today in the journal Astronomy & Astrophysics.
Thus, PSO J0309 + 27 is the strongest persistent radio source in the early universe, existing less than a billion years after the Big Bang. Observations made with the XRT telescope installed on board the Swift satellite confirmed that it is also one of the brightest sources of the early universe in the X-ray range.
Observing such blazars is extremely important. Basically, we know that for every outdoor blazar there are 100 others, differently oriented in space, making them difficult to see.
Blazars from such an early universe were most likely the kind of germs of the supermassive black holes observed in the modern universe.
The observations still carried out with the help of LBT allow us to estimate that the black hole in the center of PSO J0309 + 27 has a mass of one billion times the mass of the Sun. Thanks to this discovery, we are able to conclude that already in the first billion years of the history of the universe, there were a lot of very massive black holes emitting strong relativistic jets. The results of our observations place considerable restrictions on all theoretical models trying to explain the existence of massive black holes in the universe - concludes Belladitta.
Astronomers have discovered the remotest blazar in history
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