------------------------------------------------------------------- THE ASTRONOMER Electronic Circular No 833 1994 Apr 28 20.02UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074 INTERNET: GMH at AST.STAR.RL.AC.UK or GMH at GXVG.AST.CAM.AC.UK ------------------------------------------------------------------- FG SAGITTAE E. F. Guinan and G. P. McCook, Villanova University, report: "FG Sge, the peculiar, pulsating central star of the planetary nebula He 1-5, is undergoing another large dimming event. UBVRI photoelectric photometry, carried out with the Four College Consortium 0.8-m APT at Mt. Hopkins, shows a about 1.2-mag decrease in its V-band brightness from Mar. 23 to Apr. 19 UT. FG Sge had undergone its first recorded sudden dimming and reddening episode in Aug-Sept. 1992 (IAUC 5604, 5609, 5610, 5619, 5632) and since then has been slowly recovering in brightness. The behaviour of FG Sge is probably due to the formation of dust in its outer envelope. Its characteristics since 1992 are similar to those of R CrB-type variables." IAUC 5978 Bjorn Granslo, Norway e-mails: "The following visual observations by Norwegian variable star observers confirm that it has faded since March 1994. YYYY MM DD.DDD OBSERVATION MAG CL INSTRUM. OBSERVER 1994 01 04.71 5-6;6+6 11.0 2 M152,74x Granslo 1994 01 06.71 5-7;7+7 11.1 2 M152,74x Granslo 1994 01 08.68 5-4;7+10 10.8 2 M152,74x Granslo 1994 02 14.23 5-4 10.8: 3 C203,123x Granslo 1994 02 19.175 10.9 M152 Lauvstad 1994 03 17.12 5-4 10.8 2 C203,123x Granslo 1994 04 08.08 5-6;7+7 11.0 2 C203,80x Granslo 1994 04 13.06 6+2;7+4 11.4 2 C203,123x Granslo Time system is year, number of month and date in Universal Time. Magnitudes are calculated from Pogson's step method using the sequence of AAVSO / The Astronomer (5 = 10.4, 6 = 11.6, 7 = 11.8). CL = class is the estimated accuracy of the observation; 1 = good (+/- 0.1 mag.), 2 = fair (+/- 0.2 mag.) and 3 = poor (+/- 0.3 mag.). Observers: Bjorn H. Granslo (Fjellhamar); Andreas Lauvstad (Levanger). The position of FG Sge is R.A. = 20h11m56s, Decl. = +20d20'(2000). Observers are asked to follow this object closely during the coming weeks and months. It should be noted that there is mag. 13 star located 8" east of FG Sge." VY AQUARII This object is in outburst for the first time in a year, as indicated by the following visual magnitude estimates by A. F. Jones, Nelson, New Zealand: Apr. 22.72 UT, [13; 23.715, 11.3; 23.751, 11.5. IAUC 5979 Guy M Hurst --- 00005 --- Date: Thu, 28 Apr 1994 21:25:50 +0100 (BST)