Astronomers have discovered two giant radio galaxies in the distant universe based on observations from the MeerKAT Observatory.
The name of “radio-galaxies” comes from the fact that they emit giant beams of radio light, or jet, through interactions between charged particles and the magnetic field of the supermassive black hole in the center. Systems of this type that would grow to 22 times the diameter of the Milky Way or more have been classified into a separate group, called radio giants.
This type of galaxies are much larger than most other galaxies, but it is not easy to detect due to their very expansive structure and low light, and the limitations of the telescope. Scientists estimate that there are millions of giant radio galaxies in the universe, but only about 800 of these systems are known to date.
The two new galaxies have been observed in airspace only four times the size of the Full Moon as seen from Earth. However, they are 2 mega-parsecs wide, which is equivalent to about 6.5 million light years or 62 times the size of the Milky Way, and are located a few billion light years from us.
“Based on what we already know about the densities of giant radio-galaxies in the sky, the chances of finding two in such a small sky are extremely rare, only approximate. 0.0003%,” he pointed out. ‘team.
The MeerKAT Observatory, in operation since 2018, consists of 64 antennas – each with a diameter of 13.5 meters – dispersed in a desert area of 9,000 square meters in southwest Africa. It is one of the most sensitive telescope systems in the world, allowing it to detect weak radio signals emanating from distant galaxies.
The new discovery will give astronomers more clues as to how galaxies have changed and evolved over the course of cosmic history. Details of the study were published in the monthly notice of the Royal Astronomical Society.