THE ASTRONOMER Electronic Circular No 486 1991 Feb 21 20.46UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 9312111261 Answerback: TA G Microlink: MAG60138 JANET:GMH @ UK.AC.CAM.ASTRONOMY.STARLINK GUYH@UK.AC.SUSSEX.CLUSTER TELECOM GOLD: 10074:MIK2885 PRESTEL 256471074 ------------------------------------------------------------------- SUPERNOVA 1991F IN NGC 3458 J. Mueller reports her discovery of a supernova located 13".4 east and 12".1 south of the centre of NGC 3458 (R.A. = 10h53m.0, Decl. = +57 24', equinox 1950.0). The supernova was at blue magnitude about 18 on the Feb. 10 UT discovery plate taken with the 1.2-m Oschin Telescope in the course of the second Palomar Sky Survey by C. Brewer and J. D. Mendenhall. IAUC 5188 SUPERNOVA 1991G IN NGC 4088 Mueller also reports her discovery, again on a plate taken by Brewer and Mendenhall, of a supernova located about 37" west and 13".4 south of the center of NGC 4088 (R.A. = 12h03m.0, Decl. = +50 48', equinox 1950.0). On Feb. 10 UT, SN 1991G appeared at red magnitude about 17. IAUC 5188 SUPERNOVA 1991H IN REIZ 3080 R. H. McNaught, University of Adelaide, reports his discovery, on a U.K. Schmidt Telescope R plate taken Feb. 12.74 UT by K. S. Russell, of a supernova of mag 17.5 in Reiz 3080. The supernova is located at R.A. = 12h56m17s.24, Decl. = -10 27'51".5 (equinox 1950.0), or 2" west and 11" south of the galaxy's centre (and is identical in brightness to a nearby star located at R.A. = 12h56m16s.14, Decl. = -10 28'12".1). A Tech Pan exposure taken Feb.13.77 with the Uppsala Southern Schmidt shows the SN at mag about 18. There appears to be a faint knot (mag about 21) in the SN position on a UKST R plate exposed 1986 Mar. 15. IAUC 5188 COMET McNAUGHT-RUSSELL (1991g) Preliminary parabolic elements from 8 observations, Jan. 26-Feb15: T = 1990 Oct. 14.427 ET Peri. = 320.384 Node = 161.034 1950.0 q = 4.77030 AU Incl. = 113.386 1991 ET R.A. (1950) Decl. Delta r m1 Feb. 13 11 09.27 -22 50.0 4.090 4.865 16.4 18 11 04.54 -21 52.1 23 10 59.67 -20 49.0 4.018 4.881 16.4 28 10 54.73 -19 41.4 Mar. 5 10 49.79 -18 29.6 3.982 4.898 16.4 IAUC 5189 F.I.S. LTD Freight Informatic Systems Limited of Laindon, Basildon have today supplied written details of their proposal to take over the MICROLINK service, which will continue to run on the SPRINTMAIL computer system, after the end of this month. Several details remain unclear and I would still recommend that subscribers use JANET if at all possible. Failing this the best option appears to be TELECOM GOLD. I have sent a batch of correspondence from FIS to each person formerly maintaining a MICROLINK box and who takes our e-circulars. Please e-mail details of your arrangements for March 1 onwards as soon as possible. Those already on JANET or TELECOM GOLD are unaffected by this news note. Guy M Hurst