AT 2025abrs is a nova in M31
ATel #17493; Shatakshi Chamoli (IIA Bengaluru), Judhajeet Basu (IIA Bengaluru), G. C. Anupama (IIA Bengaluru), Sudhanshu Barway (IIA Bengaluru), Surya (IIA Bengaluru)
on 14 Nov 2025; 06:32 UT
Credential Certification: Judhajeet Basu (judhajeet.basu@iiap.res.in)
Subjects: Optical, Cataclysmic Variable, Nova, Transient
We report the spectroscopic classification of AT 2025abrs as a nova in M31. This object was discovered and reported on TNS by XOSS on 2025-10-26.56 UT at a magnitude of 18.93 (clear filter). Spectroscopic observation of this object was performed using the HFOSC instrument mounted on the 2m Himalayan Chandra Telescope, located at the Indian Astronomical Observatory (IAO), Hanle. We stacked two sets of low-resolution (R ~ 600) spectra, each with an exposure of 2100 seconds, observed on 2025-11-11. We identified H-alpha, H-beta, He and Fe II features, with H-alpha at an FWHM of ~1300 km/s, characteristic of a nova outburst.
Photometric and spectroscopic follow-up of the object is encouraged. We will continue monitoring this transient using facilities at IAO.
We thank the HCT observers for taking the time to carry out ToO observations. IAO is operated by the Indian Institute of Astrophysics, Bengaluru, India.
