Thursday 9 August 2018
Discovered 2018-05-16.320 by All Sky Automated Survey for SuperNovae (ASAS-SN), mag 17.2 at discovery
R.A. = 19h27m38s.758, Decl. = +61°56'50".07
Observer: Cedric Raguenaud, SW France
Approx mag 16.78CV ±0.01 (dmag on 257 reference stars from UCAC-4), ZP=30.256mag
0.25m/f4, QHY183C, 0.5"/pixel
3x300s, bin 1x1
From previous observation, on 2018-07-17.896, magnitude was 16.77CV.
Note: magnitude has been stable for at least 2 weeks. The location is the core of the host galaxy but SIMBAD doesn't provide magnitude for that galaxy. It's therefore not possible to know when the SN magnitude falls below galaxy core's magnitude. ASAS-SN reports a pre-discovery magnitude below limiting of 18.3 for galaxy core on 2018-05-07 08:09:36.