Discovery of an Apparent Nova in M31 Located Near Globular Cluster Bol 124
ATel #8430; K. Hornoch (Astronomical Institute, Ondrejov, Czech Republic), P. Cagas (BSObservatory, Zlin, Czech Republic)
on 18 Dec 2015; 05:26 UT
Credential Certification: Allen W. Shafter (firstname.lastname@example.org)
Subjects: Optical, Nova, Transient
Referred to by ATel #: 8441
We report the discovery of an apparent nova in M31 on co-added 4200-s CCD frames taken in Red, Green, Blue, and 7 nm wide H-alpha filters on 2015 Dec. 10.849, 10.852, 10.854, and 10.857 UT, respectively with the 0.30-m telescope + G4-16000 CCD camera at BSObservatory. The object is also visible as an elongation of a nearby bright M31 globular cluster Bol 124 on a co-added 900-s CCD frame taken on 2015 Dec. 12.693 UT with the 0.65-m telescope at Ondrejov.
The object designated PNV J00424161+4115223 is located at R.A. = 0h42m41s.61, Decl. = +41o15'22".3 (equinox 2000.0), which is 30.6" west and 46.2" south of the center of M31 (see link to Blue filter discovery image below). Although located only ~ 2" from the position of Bol 124, the connection between the two objects is uncertain due to the very high spatial density of novae near the center of M31, which increases the likelihood of a chance positional near coincidence of a nova with the globular cluster.
The following magnitudes were obtained:
2015 Dec. 7.717 UT, [19.0 (R-band); 10.849, 16.5 (Red filter, R-band magnitudes used from comparison stars); 10.852, 16.9 (Green filter, V-band magnitudes used from comparison stars); 10.854, 16.9 (Blue filter, B-band magnitudes used from comparison stars); 10.857, H-alpha = 16.3; 12.693, R = 17.3. The magnitudes have high uncertainties (~ 0.5 mag) due to blending of the nova image with Bol 124.
We thank H. Kucakova for getting images at Ondrejov on Dec. 7.717 and 12.693 UT.