Discovery of a Probable Nova in M81, M81N 2026-04a

ATel #17736; K. Hornoch, P. Fatka, H. Kucakova (Ondrejov), A. W. Shafter (SDSU)
on 2 Apr 2026; 00:27 UT
Distributed as an Instant Email Notice Novae
Credential Certification: Allen W. Shafter (ashafter@sdsu.edu)

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We report the discovery of a probable nova in M81 on a co-added 3720-s unfiltered CCD frame taken on 2026 Apr. 1.893 UT with the 0.65-m telescope at Ondrejov under poor conditions (strong moonlight and cirrus clouds).

The object designated as M81N 2026-04a = PNV J09553883+6905217 is located at R.A. = 9h55m38s.83, Decl. = +69o05'21".7 (equinox 2000.0), which is 30.3" east and 86.6" north of the center of M81 (see link to discovery image below).

Here we list the observing dates and corresponding photometry:

 
  Date [UT]    |  Mag   | Err  | Filter  | Telescope 
 
2026-03-29.918 | >21.4  |      | C       | OND 
2026-04-01.893 |  19.4  | 0.15 | C       | OND 
 

As with all extragalactic novae, follow-up spectroscopic and photometric observations to determine the nova's spectroscopic class and rate of decline (speed class) are encouraged. The OND 0.65-m is a reflecting telescope at the Ondrejov observatory operated jointly by the Astronomical Institute of ASCR and the Astronomical Institute of the Charles University of Prague, Czech Republic. It uses a Moravian Instruments G2-3200 MkII CCD camera (with a Kodak KAF-3200ME sensor and standard BVRI photometric filters) mounted at the prime focus. The unfiltered OND photometry was calibrated against R-band comparison stars from Perelmuter & Racine (1995).

Discovery image