MeerKAT finds a double relic and a strange radio circle

The MeerKAT radio telescope investigated the galaxy cluster PSZ2 G277.93+12.34 and found in it a pair of arc structures forming the so-called double relic. It can tell a lot about the past of this stellar structure. In addition, a strange radio circle was found in its image.

Double radio relic. Source: Wikipedia

Radio relic in a distant cluster

Scientists working with the South African array of MeerKAT radio telescopes have published a study of the galaxy cluster PSZ2 G277.93+12.34, near which they have noticed several very iconic objects. 

The PSZ2 G277.93+12.34 cluster is a giant array of star systems that is located at a distance of 2.5 billion light-years from us. Its mass is estimated at 360 trillion solar masses, but in general this cluster remains poorly understood. Scientists only assume that the WISEA galaxy J103230.00-433815.4 is its largest and brightest member. 

Cluster PSZ2 G277.93+12.34. Source: Koribalski et al, 2023

It was in its area that MeerKAT was sent. Other radio telescopes were also used in the study. The image obtained with their help shows that in the northeast and southwest directions from the center of the cluster there are two arcs active in the radio range, which are called radio relicts.

What are radio relics?

Radio relics are sources of synchrotron, that is, non-thermal radiation, which are often located near galaxies. They are not point-like, and represent huge arcs or rings. They are traces of past galaxy collisions.

In the case of the cluster PSZ2 G277.93+12.34, one of the relics has a length of 2.15 million light-years. And the second — 5.35 million. In total, they form a giant torn ring, that is, in fact, a double object.

According to scientists, this giant double radio relic is a consequence of the collision of galaxies on opposite courses, which led to the release and heating of a huge amount of matter. But in order to test this theory, it is necessary to study clusters at lower frequencies.

Strange radio circle

Another discovery was made in the study of PSZ2 G277.93+12.34 almost by accident. Near a cluster of galaxies, scientists have found a strange radio circle. This is the official name of such objects, of which, together with the newly discovered, only four are known.

These are giant extragalactic ring sources of radio waves, the origin and essence of which remains a mystery. For example, the new one has a size of 1.3 million light-years, that is, it is an order of magnitude larger than the entire Milky Way.

According to

Follow us on Twitter to get the most interesting space news in time