Astronomers from the Virtual Telescope Project have made a likely discovery regarding the long-term variability of the optical counterpart of the radio source NVSS J004354+404634 in the field of Messier 31. Their dedicated surveys of the galaxies Messier 31 and Messier 33 have led to the identification of several previously unknown variable stars and two possible nova candidates.

The astronomers used a new 250mm-f/4.5 astrograph with a wide field of view and carried out their observations from Manciano, Italy, where the skies are dark and ideal for star observation. Initial data was collected in August 2023, and since then, the optical counterpart of the radio source has been observed on multiple occasions.

It was found that the optical counterpart of NVSS J004354+404634 varied over several weeks, with a variation of approximately 2.5 magnitudes in the V band. According to data from other catalogs, the variation in the R band is estimated to be around 4 magnitudes.

The existence of the radio source has been confirmed by observations from the Chandra and XMM X surveys, and its redshift has been determined to be z=0.1. Astronomers speculate that the source may be a quasar, but further investigation and analysis of color indices are required to confirm this.

The researchers will continue to monitor the optical behavior of the source and examine the literature for additional details. Their efforts in studying these galaxies have not only led to the discovery of variable stars and possible novas but have also provided valuable data for future studies of these cosmic objects.

– Virtual Telescope Project
– Millions of Optical Radio/X-ray Associations (MORX) v2 (Flesch, 2023)