2010CBET.2472....1N

Koichi Nishiyama, Kurume, Japan; and Fujio Kabashima, Miyaki, Japan, report their discovery of a possible nova (mag 17.3) in M31 on seven 40-s unfiltered CCD frames (limiting magnitude 19.8) taken around Sept. 30.566 UT using a Meade 200R 0.40-m f/9.8 reflector (+ SBIG STL1001E camera), as tabulated below. An independent discovery has been reported by Guoyou Sun (Wenzhou, Zhejiang, China) and Xing Gao (Urumqi, Xinjiang, China) on 60-s unfiltered CCD survey images (limiting mag about 19) taken by Gao in the course of the Xingming Observation Sky Survey at Mt. Nanshan around Sept. 30.678 using a 35-cm Celestron C14 Schmidt-Cassegrain telescope at f/7.5 (the measurements tabulated below are by Sun), adding that nothing is visible at the same position on images taken on Sept. 9, 10, 11, 15, and 29 (no limiting magnitude given). T. Yusa, Osaki, Japan, also reports his confirmation of M31N 2010-09b on unfiltered CCD frames (limiting mag 18.2) taken on Oct. 1.42, following a request from Kabashima and Nishiyama, using a 0.30-m f/9.9 Cassegrain telescope (+ SBIG STL-1001E camera), with his data also tabulated below; he has posted his image at the following website URL: http://space.geocities.jp/yusastar77/PNinM31_101001.htm. Wolfgang Pietsch, Max-Planck-Institut fuer Extraterrestrische Physik, reports a pre-discovery observation from CCD images obtained with the robotic 60-cm telescope of the Livermore Optical Transient Imaging System (cf. CBET 2124), also tabulated below.

---------------------------------------------------------------------------— 2010 UT R.A. (2000.0) Decl. Mag. Observers ---------------------------------------------------------------------------— Sept. 30.412 0 43 45.53 +41 07 54.7 17.7 Pietsch et al. 30.566 0 43 45.52 +41 07 54.9 17.3 Nishiyama, Kabashima 30.678 0 43 45.1 +41 07 54.4 17.8 Sun, Gao Oct. 1.416 0 43 45.54 +41 07 55.0 16.9 Yusa ---------------------------------------------------------------------------—

Nishiyama notes that M31N 2010-09b is located 690" east and 494" south of the center of the galaxy M31. Additional magnitudes for M31N 2010-09b: 1986 Nov. 27, [18.9 (Digitized Sky Survey, red; via Nishiyama and Kabashima); 1993 Oct. 21, [18.4 (DSS, infrared; via Nishiyama and Kabashima); 2010 Sept. 21.570, [19.2 (Nishiyama and Kabashima); 28.606, [19.2 (Nishiyama and Kabashima); Oct. 1.516, 16.9 (Nishiyama and Kabashima); 1.564, 16.8 (Nishiyama and Kabashima).