Discovery of a Probable Nova in M31
ATel #8877; K. Hornoch (Astronomical Institute, Ondrejov, Czech Republic), J. Vrastil, K. Honkova, H. Kucakova (Astronomical Institute, Charles U., Prague, Czech Republic)
on 27 Mar 2016; 21:31 UT
Credential Certification: Allen W. Shafter (ashafter@mail.sdsu.edu)
Subjects: Optical, Nova, Transient
We report the discovery of a probable nova in M31 on a co-added 780-s R-band CCD frame taken on 2016 Mar. 26.773 UT with the 0.65-m telescope at Ondrejov.
The object designated PNV J00424805+4117134 is located at R.A. = 0h42m48s.05, Decl. = +41o17'13".4 (equinox 2000.0), which is 42.0" east and 64.9" north of the center of M31 (see link to discovery image below).
The probable nova is blended with nearby star (having R = 17.3 mag) located at coordinates R.A. = 0h42m48s.03, Decl. = +41o17'14".1 (equinox 2000.0) on Ondrejov images. We verified these are two different objects (and thus it is not an outburst of the nearby star) by measuring shift of the centroid of 0.5" before and after the outburst of the nova. Centroids of other nearby stars of similar brightness remain constant to within 0.1".
To get the photometry of the PNV J00424805+4117134, we subtracted the mean flux of the constant star from the measured total flux of the blend yielding the following R-band magnitudes:
2016 Mar. 8.818 UT, [19.6; 16.766, 17.3 ± 0.4; 17.768, 16.9 ± 0.3;
18.769, 17.0 ± 0.4; 19.772, 17.4 ± 0.4; 26.773, 17.5 ± 0.3.
Discovery image
