Electronic Telegram No. 5729 Central Bureau for Astronomical Telegrams Mailing address: Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network V488 SAGITTAE = NOVA SAGITTAE 2026 = PNV J19450648+1822422 Katie Barnhart, Kirill Sokolovsky, Darien Perla, Pragati Acharya, John Worley, Vallia Antoniou, and Elias Aydi, Texas Tech University, report the discovery of a possible nova (mag 9.0) on multiple unfiltered CMOS camera images obtained on Aug. 25.1 UT with dual Rokinon 135-mm-f.l. camera lens in the course of the New Milky Way (NMW) Survey. The variable is located at R.A. = 19h45m06s.48, Decl. = +18d22'42".2 (equinox J2000.0), and the discoverers provide the following magnitudes: Aug. 24.126, [14.0; 25.128, 9.0; 25.129, 9.0; 25.138, 8.9; 25.140, 8.9. The unfiltered-magnitude zero-point was calibrated using V magnitudes of Tycho-2 stars in the field. The discovery images and finder charts are available at the following website URL: https://tau.kirx.net/img/PNVJ19450648+1822422/. The transient appears to coincide with the variable star Gaia DR3 1824166210904571136 (position end figures catalogued as 06s.49, 42".1 at epoch 2016.0), which varies between G magnitudes 19.3 and 20.8. The NMW-TexasTech survey operates at the Preston Gott Skyview Observatory near Shallowater, TX, USA. Follow-up CMOS camera photometry by Sokolovsky et al. on Aug. 25.303 with a 0.3-m telescope at the same location: B = 8.18 +/- 0.01, V = 7.75 +/- 0.02, R = 7.40 +/- 0.02. The variable received the preliminary designation PNV J19450648+1822422 when it was posted to the Central Bureau's TOCP webpage. Additional camera photometry reported to the Central Bureau for PNV J19450648+1822422: Aug. 24.457 UT, [13.0 (Y. Nakamura, Kameyama, Mie, Japan; 8-s CMOS camera exposure taken with a 135-mm-f.l. f/4 lens; communicated by I. Endoh and M. Sato (National Astronomical Observatory of Japan); 25.444, V = 7.42 (K. Yoshimoto, Yamaguchi, Japan, CMOS camera + 135-mm-f.l. f/3.5 lens); 25.450, B = 7.89, V = 7.34, R = 7.06, I = 6.64 (Yoshimoto; 0.30-m f/4 reflector + CMOS; position end figures 06s.48, 42".2); 25.455, 7.4 (Nakamura; three unfiltered 8-s CMOS camera exposures; limiting mag 13.0; position end figures 06s.46, 43".2); 25.488, TG = 7.4, TB = 7.9, TR = 7.0 (T. Yusa, Miyagi, Japan; 0.05-m f/5 refractor; Seestar tri-color G, B, R channel; APASS-V, B, R reference stars; position end figures 06s.49, 42".2 using ATLAS reference stars); 25.532, TB = 8.27, V = 7.68 and TR = 7.38 (A. Pearce, Nedlands, W. Australia, 0.05-m refractor + CMOS; position end figures 06s.48, 41".9 using Gaia DR2 catalogue stars; Gaia 1824166210904571136, G mag 19.8, is about 0".2 from this presumed nova); 25.804, V = 7.6 (G. Pappa, Pedara, Italy; Canon 760D DSLR camera + 0.3-m f/5 lens); 26.470, 7.1 (K. Imamura, Tokushima, Japan; from RGB image, calibrated against UCAC4 and Tycho-2 V magnitudes; DWARF mini LAB telescope). M. Reszelski, Szamotuly, Poland, reports visual mag 7.2 on Aug. 25.894 UT using 25x100 binoculars for NV J19450648+1822422. K. Taguchi (Kyoto University) and A. Arai (National Astronomical Observatory of Japan) report that spectroscopy of PNV J19450648+1822422 obtained on Aug. 25.431 UT with the 3.8-m infrared Seimei telescope at Mt. Chikurinji (Okayama, Japan) show this to likely be a nova, although with many absorption features; H_alpha and H_beta have P-Cyg profiles of about -1500 and -1300 km/s, respectively (cf. https://www.astronomerstelegram.org/?read=18008). E. Kazarovets (Institute of Astronomy, Moscow) writes that the permanent GCVS designation V488 Sge has been assigned to PNV J19450648+1822422. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2026 CBAT 2026 August 26 (CBET 5729) Daniel W. E. Green