Each of these white dots is an active supermassive black hole. Not only that, but each of these black holes is "devouring" matter at the center of a galaxy millions of light years away.
A total of 25,000 such bright dots. Astronomers have spent many years researching and have just created this map, the most detailed map ever to be found of black holes at low radio frequencies.
Astronomer Francesco de Gasperin of the University of Hamburg, Germany, said, "This is the result of years of working with extremely difficult data. We have to create new ways to transform these data. radio signal into image of the sky ".
When black holes are not very active, they do not emit a radiation signal that we can obtain, so it is difficult to find them. When a black hole intensifies its sedimentation, wraps around itself a disk of dust and gas, it looks a lot like a vortex at the manhole, and the enormous eddy force produces radiation across the wavelengths of which they are. can be found in the vast universe.
The photo above is special in that it covers the extremely low radio wavelengths detected by the LOFAR telescope system in Europe. This is an interferometer network of about 20,000 radio antennas scattered across 52 locations in Europe.
Currently, LOFAR is the only radio telescope network capable of capturing high resolution and deep images at frequencies below 100 MHz. Because it is placed on the ground, LOFAR has a very large obstacle that space telescopes do not encounter, the ionosphere. The ionosphere can cause extremely low frequency radio wavelengths to be reflected back into space. Frequencies that do not pass through the ionosphere fluctuate depending on atmospheric conditions.
To get rid of this problem, the team used supercomputers to run algorithms that correct ionosphere interventions every four seconds. Thus we can see how much of the 256-hour period LOFAR looks up into the sky is the number of corrective calculations.
But there is another benefit to correcting the errors caused by the effects of the ionosphere. That is, astronomers can study the ionosphere itself, the wavelengths that can pass through the ionosphere, the relationship of this atmosphere to the solar cycles. In addition, this is new data on all kinds of objects and astronomical phenomena, as well as undiscovered objects below 50MHz.
The end result of this study will promote a variety of fields of astronomical research. Researchers will be able to learn about more than a million low-frequency radio spectrums, gain a deeper understanding of the physical models of galaxies, clusters and many other fields.
