Electronic Telegram No. 1816 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://www.cfa.harvard.edu/iau/cbat.html V5582 SAGITTARII = NOVA SAGITTARII 2009 No. 2 Guoyou Sun, Wenzhou, Zhejiang, China; and Xing Gao, Urumqi, Xinjiang, China, report the discovery of a possible nova (mag approximately 11.5) on several 60-s survey images (limiting mag about 13.5) taken by Gao in the course of the Xingming Nova Survey (Mt. Nanshan) on Feb. 23.947-23.963 UT with a Canon EOS 350D camera (+ 135-mm f/2 lens at ISO 800). Using a 10.7-cm f/2.8 camera lens, their images taken during Feb. 27.96-Mar. 6.97 yield the following position for the variable: R.A. = 17h45m05s.42 +/- 0s.12, Decl. = -20o03'22".0 +/- 0".6 (equinox 2000.0); an image obtained on Apr. 28 by Sun with a 1-m f/8 reflector at Weihai yields position end figures 05s.40, 21".5. Nothing was visible at this location on images taken by the discoverers on 2008 Aug. 23, Sept. 4, 25, and Oct. 3 (limiting mag presumably also about 13.5); they report that nothing is visible at this position on Digitized Sky Survey images from 1950 June 19 (limiting red mag 20.0), 1980 Aug. 2 (limiting infrared mag 19.5), and 1991 Aug. 2 (limiting red mag 20.8). Additional available magnitudes from Sun and Gao for the variable: Feb. 27.960, 12.1; 28.968, 12.0; Mar. 2.963, 13.0; 3.964, 12.8; 6.968, 13.1; 22.949, 11.6; 26.950, 12.1; 27.947, 12.5; Apr. 28.837, 13.2. The discoverers have posted images at the following website URL: http://www.xjltp.com/XM09AA/XM09AA.htm. Following posting on the Central Bureau's unconfirmed-objects webpage, other observers have reported their observations of this variable. K. Nishiyama (Kurume, Fukuoka, Japan) and F. Kabashima (Miyaki, Saga, Japan) report (via S. Nakano, K. Kinugasa, and H. Yamaoka) the following magnitudes from their CCD frames taken with a patrol camera (+ 106-mm-f.l. f/4 lens; limiting mag 12.9-13.8) in February and with a 40-cm reflector afterwards: Feb. 20.855, 10.9; 25.847, 10.4; 28.859, 11.4; Mar. 14.860, 13.2; May 19.665, 14.0; 22.728, 13.7. With the larger instrument, Nishiyama and Kabashima measured position end figures 05s.40, 21".7. G. Sostero, E. Guido, and P. Camilleri write that they obtained position end figures 05s.42, 22".0 and magnitudes R = 12.2, B = 13.8 from images obtained remotely on Mar. 13.44 with a 25-cm f/3.4 reflector at the GRAS Observatory near Mayhill, NM, U.S.A.; comparison with an Anglo-Australian Observatory Schmidt red plate (limiting magnitude about 20), obtained on 1991 Aug. 2, shows an extremely faint object at position end figures of 05s.38, 23".4 at the threshold of the plate (comparison images are posted at website URL http://tinyurl.com/defzqs. K. Kinugasa, S. Honda, and O. Hashimoto, Gunma Astronomical Observatory (GAO); and Y. Takeda, National Astronomical Observatory of Japan, obtained a low-resolution spectrum (range 400-800 nm, resolution about 500) of this object using the GAO 1.5-m telescope (+ GLOWS) on May 26.7 UT, which shows strong emission lines of Balmer series, [O III], [N II], and He I -- suggesting that the object is a classical nova well past maximum. N. Samus informs the Central Bureau that the GCVS team has assigned the designation V5582 Sgr to this nova. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 May 29 (CBET 1816) Daniel W. E. Green