At first sight it may seem like a “banal” astronomical image of a night sky, covered with stars. In fact, its nature is much more complex and it took many years to achieve such an incredible result: here is the most detailed map of black holes ever obtained at low frequencies.
To add further amazement to this image we will tell you that it is not just any black holes, but every bright dot you see is a supermassive black hole currently active, which is devouring and satiating with star material in the center of its gal Each of them is millions of light years away from us, and from this small portion there are more than 25 thousand.
As you can see in the opening, it is the most detailed map ever obtained of black holes, obtained by studying ultra-low radio frequencies. Its development was completed about a year ago, in the early 2021 months, and it took several years of study and the use of the LOW Frequency ARray (LOFAR). It is a complex interferometric network composed of about 20,000 radio antennas, distributed in 52 locations throughout Europe.
“This is the result of many years of work on incredibly difficult data,” explained astronomer Francesco de Gasperin of the University of Hamburg in Germany. “We literally had to invent new methods to convert radio signals into images of the sky.” To overcome all the adversities of the measurements (such as atmospheric interference, those of the star gases, etc.), scientists used some supercomputers capable of correcting ionosphere interference every four seconds.
The research was published in Astronomy and Astrophysics last April 2021, opening the doors for even more in-depth studies: over 1 million low frequency radio spectra are waiting to be analyzed, which include not only black holes, but also
This experiment represents a unique attempt to explore the sky at ultra-low frequency, and it seems that the results are highly promising. If the world of these dark cosmic monsters fascinates you, here you will discover when the first black holes were formed.