According to AAVSO Special Notice #164 just sent, there is a possible nova candidate in Sagittarius. It was discovered by Koichi Nishiyama, Kurume, Fukuoka-ken, Japan, and Fujio Kabashima, Miyaki-cho, Saga-ken, Japan, at unfiltered magnitude 7.7 on two 60-second frames taken Aug. 6.494 and 6.495 UT. They confirmed the discovery on five frames taken around Aug. 6.494.
Brian Marsden announces in CBET No. 1899 the independent discovery of a possible nova (Nova Sagittarii 2009 No. 3) by Koichi Nishiyama, Kurume, Fukuoka-ken, Japan, and Fujio Kabashima, Miyaki-cho, Saga-ken, Japan, at unfiltered magnitude 7.7 on two 60-second frames taken Aug. 6.494 and 6.495 UT. They confirmed the discovery on five frames taken around Aug. 6.494. No motion was seen during 80 minutes and nothing was visible at this location down to 12.7 on survey frames taken July 22.531 and 29.584 UT. Nothing was seen on the DSS (POSS2/UKSTU red), or in ASAS, AAVSO VSX, SIMBAD, 2MASS and USNO-B1.0 catalogues, although the USNO-B1.0 shows a faint star (I = 12.45) nearby (at end figures 07.509s, 33.13″). Coordinates (from Nishiyama and Kabashima) are: RA = 18h 07m 07.67s, Dec = -33d 46m 33.9s (2000.0)
According to Elizabeth Waagen of AAVSO, Grzegorz Pojmanski, Dorota Szczygiel, and Bogumil Pilecki, Warsaw University Astronomical Observatory, observed by ASAS3 at V = 7.78 on Aug. 6.182 UT at the approximate position RA = 18h 07m 08s, Dec = -33d 46.6m. Nothing was visible on Aug. 4.152 UT. Leonid Elenin, Moscow, also confirmed (via vsnet-alert 11371) the presence of the object using a remote astrograph in Pingelly, Australia, providing position end figures 07.67s, 34.9s, +/-0.14″. This object has been assigned the name VSX J180707.6-334633 with the AUID 000-BJP-536. Please report observations to the AAVSO International Database using the name Nova Sgr 2009 No. 3 or VSX J180707.6-334633. The ASAS light curve and images can be accessed here. A sequence has not yet been established for this object, but additional finder charts may be plotted by entering the coordinates into VSP.