THE ASTRONOMER Electronic Circular No 403 1990 April 18 18.46UT Microlink:MAG60138 JANET:GUYH at UK.AC.SUSSEX.CLUSTER Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 94082518 Answerback: TAGUY ------------------------------------------------------------------ PROBABLE NOVA IN SCORPIUS W. Liller, Vina del Mar, Chile, reports his discovery with PROBLICOM of a probable nova at R.A. = 17h50m57s, Decl. = -30 48.3 (equinox 1950.0). Magnitudes from 2415 film (+ red filter): Apr. 9.25 UT, [12; 17.19, 10.2. He adds that this may be a recurrence of N Sco 1954 = NSV 09808 (IAUC 1471), though the position of that object is poorly known (Duerbeck 1987, Space Sci. Rev. 45, 1). IAUC 4995 Editor: NSV 09808 was discovered by P.Wild, Mount Palomar Observatory on objective prism plates taken on 1954 August 30. The position was estimated as: RA 17h50m27s DEC -30 44'57"(1950) and discovery magnitude as 13.8mpg CI GEMINORUM This nova-like variable (RA 06h26m54s DEC +22 21'(1950)) was found by C.Hoffmeister with maximum recorded on 1940 Jan 3 at 14.7mpg. Further checks by Hoffmeister of 166 plates 1935 Nov 1 to 1944 Feb 24 failed to reveal further outbursts. W.Wenzel, Sternwarte Sonneberg, reports analysis of Sonneberg plates taken on 70 nights 1962.9-1966.7 and 1980.0 to 1989.2 in a search for CI Gem. He finds further outbursts: 1963 Oct 5, 16.5 mpg (2 plates) 1966 Feb 23, 16.5 mpg 1986 Dec 3, 14.5 mpg Duerbeck finds minimum light as B=18.5 on POSS. Wenzel concludes that it may be an SU UMa-type dwarf nova with a period of 100 days. IBVS 3440 Observers are urged to monitor this system and photographs to assist in chart development would be helpful. Guy M Hurst