Just few days after the discovery of the nova in M31 designated as AT2020xyv, we report our discovery of another possible nova in M31 on a 240-s R-band CCD frame taken on 2020 Oct. 30.91 UT with the 0.5 m f/8 Ritchey Chretien + CCD FLI PL4240 at MPC Code L07 (Osservatorio Salvatore di Giacomo, Agerola, ITALY), with magnitude R = 18.48 +- 0.10 at coordinates:
R.A. = 00 45 28.80, Decl.= +41 54 10.0 (equinox 2000.0; Gaia DR2).
This transient PNV J00452880+4154100 has been independently discovered by Darnley et al. as reported on ATel #14130 of 31 Oct 2020; 07:32 UT and identified by them as the eruption of recurrent Nova M31N 2008-12a.
Our discovery image of this transient (click on it for a bigger version):
M31N 2008-12a is a remarkable recurrent Nova in the Andromeda Galaxy with the "shortest interoutburst time of any known recurrent nova. Since its discovery in December 2008 by two Japanese amateur astronomers, Koichi Nishiyama and Fujio Kabashima, a total of 13 subsequent outbursts have been observed. The mean time between observed eruptions (all observed between late August and December) is 364+/-52 days".
by Antonio Catapano, Ernesto Guido, Luca Izzo