Galaxy Reclassified After Jet Direction Changes

A galaxy has been reclassified based on activity in its core as a result of an interesting finding made by a group of international scientists. Once categorized as a radio galaxy, PBC J2333.9-2343 is now categorized as a massive radio galaxy featuring a blazar at its center. A relativistic jet from an active galactic nucleus (AGN) pointed at an observer is known as a blazar. In this instance, the jet has abruptly changed course, moving from above the horizon to aim right at us.

The charged particles that make up blazar jets travel at speeds that are almost as fast as light. They revolve in a powerful magnetic field while emitting radiation over the whole electromagnetic spectrum. The emission from the remainder of the galaxy can easily outpace that coming from the jet when it is heading in our direction. It may lead to high-intensity flares that are more powerful than those from other radio galaxies. This change in direction has caused the galaxy to be reclassified.

It has been known for jets to change course in the past. However, this is the first time that phenomenon has been seen without implying the existence of two distinct periods of jet activity. Astronomers employed a variety of telescopes to view and collect data on this mysterious galaxy across the electromagnetic spectrum. The objective was to obtain more data regarding it. These telescopes included radio, ultraviolet, optical, infrared, x-ray, and gamma-ray telescopes. The scientists next examined the characteristics of PBC J2333.9-2343 to extensive samples of blazar and non-blazar galaxies given by the ALeRCE project in Chile.

The researchers came to the conclusion that this galaxy features a brilliant blazar at its center and two lobes on either side of the jet. The lobes are remnants of earlier radio activity. This is because they are associated with the former jets and no longer get energy from the nucleus’ emission. In contrast to normal radio galaxies, the AGN no longer drives the lobes. The team has not yet identified the cause behind the abrupt change in the jets’ path. However, they hypothesize it may have been a galaxy merger event or another comparably massive object. Furthermore, it could be the result of an intense outburst of activity in the core of the galaxy after a period of inactivity.

According to the paper’s lead author, Dr Lorena Hernández-Garca, they began to examine this galaxy as it revealed strange traits. They had to make a lot of observations to verify their hypothesis that the relativistic jet of the supermassive black hole had altered course. The fact that the nucleus is no longer feeding the lobes, she continues, “shows that they are quite old. These are remnants of earlier activity, whereas the formations found nearer the nucleus are younger, active jets.”