V. Lipunov, D. Denisenko and E. Gorbovskoy (SAI MSU) report the discovery by V. Yecheistov of a possible Nova in M31 (NGC 224) on the unfiltered images (180 sec exposures, limiting magnitude 18.8) obtained on 2013 Aug. 26.704 and Aug. 26.718 UT by MASTER-Amur robotic telescope (double 0.40-m f/2.5 reflector + 4K*4K CCD). The new object is located at R.A.=00h37m12s.10, Dec.=+40o39'04".0 (J2000.0) which is 3781" west and 2224" south of the nucleus of M31. Is was also observed by the same telescope on Aug. 28.727 UT. The magnitudes (unfiltered with red zero point) are as follows: Aug. 26.704, 17.9; 26.718, 17.8; 28.727, 16.7; 28.757, 16.8. Object was not present on Aug. 13.717 unfiltered image to the limiting magnitude 19.0. There is nothing at this position on the digitized Palomar plates (m_lim~21) and on SDSS image (m_lim~23). MASTER-Amur discovery, confirmation and reference images are available at this URL: http://master.sai.msu.ru/static/OT/003712.10403904.0.png with more details in ATel #5355, see http://www.astronomerstelegram.org/?read=5355 (MASTER OT J003712.10+403904.0).
D. Denisenko, V. Lipunov and E. Gorbovskoy also report additional magnitudes from MASTER-Amur follow up images (180-sec exposures) obtained on 2013 Sep. 02: 02.689, 18.0; 02.717, 17.9. The object appears to have reached its maximum light around Aug. 28, having faded by 1.3m in the next five days.
This transient was observed on 2013 09 13.828 by Gianluca Masi, Francesca Nocentini and Patrick Schmeer, remotely using the 17" robotic unit part of the Virtual Telescope Project facility in Ceccano, Italy. Unfiltered images show a source at mag. 19.0 (R mags for the reference stars from UCAC-4). We also performed astrometry, getting the following end figures: 12.08s 04.7" (J2000.0, mean residuals of 0.15" on both axes).