Central Bureau for Astronomical Telegrams

CBAT "Transient Object Followup Reports"

TCP J21582885+2954056

TCP J21582885+2954056   2024 01 10.6583*  21 58 28.85 +29 54 05.6  13.3 U             Peg       9 0

2024 01 10.7777

The CV=13.3 transient was discovered in nine 20sec exposure images obtained between 2024-01-10.6572 and 2024-01-10.7777 UTC using a 135mm f/2.0 telephoto lens attached to an unfiltered SBIG STL-11000 CCD. This is the secondary NMW survey camera ( http://scan.sai.msu.ru/nmw/ ) operating at the Astroverty astrofarm in Nizhnii Arkhyz, Karachay-Cherkessia, Russia. The previous image of this field, captured on 2024-01-07.6840 using the same camera, shows no transient brighter than CV~14.5 at the specified position. The CV unfiltered magnitudes were calibrate using V magnitudes of an ensemble of Tycho-2 stars in the field. The plate-solved FITS images and finder charts may be found at http://scan.sai.msu.ru/~kirx/img/TCPJ21582885+2954056/ The transient may be associated with a star PS1 143883296197442755 (g=21.9, r=21.8, i=21.5) located 1.7" from the measured position (within the expected astrometric uncertainty of a few arcsec). Given the low total Galactic extinction in this direction, A(V)= 0.33 (Schlegel, Finkbeiner & Davis 1998, ApJ, 500, 525), and the possible association to a Pan-STARRS source indicating an outburst amplitude of approximately 8.5mag, we suggest that the transient could be a previously unknown WZ Sge-type dwarf nova. ---- Stanislav Korotkiy (Astroverty, Ka-Dar), Kirill Sokolovsky (UIUC, SAI MSU), Sergei Ostapenko