A newly discovered radio signal source near the galaxy's centre, ASKAP J173608.2-321635, has puzzled astronomers due to its unique properties. The source was found using the Australian Square Kilometre Array Pathfinder (ASKAP), a highly sensitive radio telescope designed to explore the depths of the radio Universe. ASKAP has previously made discoveries such as Odd Radio Circles and unidentified galaxies.
ASKAP J173608.2-321635 emits radio waves for extended periods and then suddenly disappears. The signal is highly polarized, indicating a twisted orientation of the electromagnetic wave. The object is elusive and has not been detected before the ASKAP observations. Follow-up observations using different radio telescopes confirmed the detection but provided no additional information. The source did not appear in X-ray, near-infrared, or archival radio data, leaving astronomers puzzled.
The polarization of the signal suggests the involvement of scattering and magnetization, possibly due to dust and magnetic fields in the interstellar medium. However, the nature of the source itself remains unknown. Known types of stars that vary in radio wavelengths, such as flaring stars or close binaries, are unlikely explanations due to the non-detection in X-ray and near-infrared wavelengths. Pulsars, which are neutron stars emitting regular radio beams, also do not fit the observed characteristics of ASKAP J173608.2-321635.
One possibility is that the source belongs to a class of enigmatic signals called Galactic Center Radio Transients (GCRTs), which share some similarities with ASKAP J173608.2-321635. GCRTs are signals detected near the galactic centre that has yet to be fully explained. If the newly discovered source is indeed a GCRT, its detection by ASKAP could assist in identifying more of these sources and unravelling their nature.
Further observations and comparisons with other regions are necessary to understand the uniqueness of ASKAP J173608.2-321635 and its potential relation to the Galactic plane. Increasing the frequency of surveys and analyzing the results will aid in deciphering the nature of this mysterious source.