Electronic Telegram No. 1761 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 V1413 AQUILAE U. Munari, A. Siviero, P. Ochner, and M. Valentini, Istituto Nazionale di Astrofisica, Padova Astronomical Observatory; and S. Dallaporta, "Asiago Novae and Symbiotic Stars" (ANS) collaboration, report that the symbiotic nova V1413 Aql, on egress from the eclipse of the white dwarf by the M5 III cool-giant companion (center of eclipse on Mar. 7, orbital period 434.1 days; cf. Munari 1992, A.Ap. 257, 163), is not leveling off at the constant magnitude (V = 13.5) that it has been keeping outside of eclipses over the last several years; it is instead on a linear rise in brightness (0.07 mag/day), characterized by the following values for the last few days: Apr. 4.114 UT, V = 13.295, B-V = +0.915, V-I_c = +2.113, R_c-I_c = +1.156; Apr. 8.108, V = 12.994, B-V = +0.923, V-I_c = +1.897, R_c-I_c = +1.031; Apr. 10.104, V = 12.906, B-V = +0.936, V-I_c = +1.854, R_c-I_c = +1.003. V1413 Aql (= AS 338) entered in 1978 its still-ongoing outburst, characterized by two maxima at V = 11 around 1982-1983 and 1995-1996 (cf. IAUC 6151, 6165) and very slow declines thereafter to V = 13.5 (which is two magnitudes brighter than the long-term pre-outburst quiescence value of V = 15.5 (cf. Siviero et al. 2007, Baltic Astronomy 16, 55). The current new rise in brightness could mark the beginning of a long ascent to a third maximum that, extrapolating from the previous two, could be reached at V = 11 in about one year. Early signs of a reprisal in brightness can be glimpsed in the VSNET and AAVSO data collected at the end of 2008. The present phase is monitored with the high- and low-resolution Boller & Chievens and echelle spectrographs of the Asiago 1.22-m telescope of the University of Padova and the INAF 1.82-m telescope of the Astronomical Observatory of Padova. The spectral appearance is identical to that of the initial 1993 rise to its 1995-1996 maximum (cf. IAUC 5884). In the last spectrum taken on 2009 Apr. 9.11, the H_beta flux was 6.76 x 10**(-13) erg cm**(-2) s**(-1), and the flux ratio (H_beta):([O III] 500.7-nm):(He I 587.6-nm):(He II 468.6-nm) was 1.00:0.73:0.42:0.12. Gaining in experience from the previous two maxima of V1413 Aql, a new maximum should be characterized by a doubling of this H_beta flux and the above flux ratio changing to 1.00:0.15:0.35:0.00. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 April 11 (CBET 1761) Daniel W. E. Green