THE ASTRONOMER Electronic Circular No 500 1991 Mar 26 20.36UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 9312111261 Answerback: TA G JANET BOXES: GMH at UK.AC.CAM.ASTRONOMY.STARLINK or GUYH at UK.AC.SUSSEX.CLUSTER TELECOM GOLD: 10074:MIK2885 PRESTEL 256471074 ------------------------------------------------------------------- NOVA HERCULIS 1991 Further to yesterday's announcement, the Central Bureau advise us that Matsuo Sugano (Japan) independently discovered this nova which he had recorded on a photograph of Mar 24.781UT at magnitude 5.4. It is evident that George Alcock's discovery represented the first known visual observation of the nova. This is the fifth nova to be found by Alcock (excluding independent discovery of an outburst of RS Oph in 1985) and is in addition to five comet discoveries. George reports that since the beginning of 1989 he has logged 553 hours 38 minutes of observing time. Rob McNaught, Australia, e-mails that he has secured a precise position from a 10 second exposure with the Uppsala: RA 18h44m11.83s DEC +12 10'45.0"(1950) He has checked the Palomar Sky Survey and finds the nearest candidates are: Star 1 mag approx 19 18h44m12.05s DEC +12 10 44.3 (1950) 2 14 18 44 11.67 +12 10 52.0 3 16 18 44 11.92 +12 10 52.1 (partly obscured by star 2) He adds that there is no blue star near the nova's position but that star 1 is somewhat brighter on the red print than the blue. Further estimates: Mar 25.67, 6.5 (McNaught); 25.80, 6.6 (McNaught); 26.13, 7.1 (Alan Pickup, Edinburgh). The initial comparison stars are labelled and based on the AAVSO Atlas values: Star Mag Object A 3.0 zeta Aql B 4.0 epsilon Aql C 5.4 Double near zeta D 5.9 North of C E 6.8 Preceding KO Aql F 7.0 North of KO Aql G 7.5 Following KO Aql H 8.2 North preceding VW Aql J 9.0 Due north of VW Aql Sequence reference: TA 910325 DX AND An unconfirmed report has been received from Finland by Martin Mobberley of a possible outburst of this star. Professional astronomers urgently need further estimates and previous negative results to assess the present activity, Guy M Hurst