ASASSN-18ix (N:/UG:)
RA 18h26m31.10s, DEC -46°53'03.3" (J2000.0)
2018 April 22.35 UT, V= 12.6 mag
Discoverer: All Sky Automated Survey for SuperNovae (ASAS-SN)
"ASAS-SN Discovery of a Possible Galactic Nova ASASSN-18ix":
http://www.astronomerstelegram.org/?read=11561
ASASSN-18ix 20180421.39 <167V ASN
ASASSN-18ix 20180422.05 129g ASN
ASASSN-18ix 20180422.24 125g ASN
ASASSN-18ix 20180422.35 126V ASN
GSC2.3 SC92162262 (Bj= 21.42 mag), which is 2.2" away from the ASAS-SN position at RA 18 26 30.892, DEC -46 53 03.83 (J2000.0) may be the progenitor.
Spectroscopy, multiband photometry, and precise astrometry are urgently required.
Clear skies,
Patrick
Brian Skiff writes about GSC2.3 SC92162262 as the possible progenitor (vsnet-alert 22103):
"This star does appear to be relatively blue on the southern Schmidt survey images (invisible or barely visible on DSS2 red and far-red plates, but readily visible on the blue plate). The GSC-2.3 and SuperCOSMOS coordinates compared:
18 26 30.89 -46 53 03.8 GSC-2.3
18 26 30.93 -46 53 03.5 SuperCOSMOS, epoch 1974.612
Both show blue magnitude 21.4 from independent scans of the plates."
"Just imaged it, appears quite blue under high saturation. My guess is not a nova. Magnitude around 12.9 in green channel (~V). Definitely fainter than the 12.6V in ATel."
Looks like a high-amplitude dwarf nova outburst (UGWZ?). Time-resolved photometry and precise astrometry have now the highest prority.