THE ASTRONOMER Electronic Circular No 425 1990 June 27 19.40UT Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone: (0256)471074 Int:+44256471074 Telex: 94082518 Answerback: TAGUY Microlink: MAG60138 JANET:GMH @ UK.AC.CAM.ASTRONOMY.STARLINK or GUYH@UK.AC.SUSSEX.CLUSTER --------------------------------------------------------------------- COMET McNAUGHT-HUGHES (1990g) Preliminary parabolic orbital elements by B. G. Marsden, Center for Astrophysics, from 9 observations June 19-23: T = 1991 Mar. 6.45 ET Peri. = 27.31 Node = 234.52 1950.0 q = 2.4159 AU Incl. = 131.47 1990 ET R.A. (1950) Decl. Delta r m1 June 28 16 59.81 -63 58.5 2.789 3.600 16.8 July 3 16 39.03 -62 37.5 8 16 20.62 -61 00.9 2.762 3.527 16.7 13 16 04.73 -59 12.2 18 15 51.33 -57 15.2 2.776 3.455 16.6 23 15 40.25 -55 13.3 28 15 31.24 -53 09.6 2.826 3.384 16.5 IAUC 5037 PERIODIC COMET JOHNSON (1990h) J. Gibson, OAO Corporation and Jet Propulsion Laboratory, reports his recovery of this comet with the Palomar 1.5-m reflector(+ CCD + Gunn r filter). The comet's image is stellar within the limits of seeing, and the following positions are in agreement with the orbital elements on MPC 12123 (ephemeris on MPC 15732): 1990 UT R.A. (1950) Decl. m2 June 17.37291 19 06 08.34 -15 15 42.3 18 18.37122 19 05 35.29 -15 21 07.9 IAUC 5038 SUPERNOVA 1990N IN NGC 4639 A. Maury, Observatoire de la Cote d'Azur (OCA), reports the discovery by E. Thouvenot of a supernova in NGC 4639 (R.A. = 12h40m21s, Decl. = +13 31'.9, equinox 1950.0) on a 5-min unfiltered CCD exposure taken by C. Buil, A. Maury, and L. Brunetto with the Pic du Midi 0.6-m telescope on June 22.964 UT. A IIa-O plate taken by D. Albanese on June 23.93 with the OCA 0.90-m Schmidt telescope shows the object at mag about 15.5 and located 65" east and 1" south of the galaxy's center. IAUC 5039 SUPERNOVA 1990O IN MCG +03-44-003 J. Mueller reports her discovery of a supernova (mag 17) in MCG +03-44-003 (R.A. = 17h13m.3, Decl. = +16 22', equinox 1950.0), located 20".2 east and 3".4 south of the galaxy's center. SN 1990O was found on a blue plate taken June 22 UT in the course of the second Palomar Sky Survey with the 1.2-m Oschin Schmidt Tele- scope. IAUC 5039 SUPERNOVA 1990P IN ANONYMOUS GALAXY R. H. McNaught reports his discovery of an apparent supernova on a U.K. Schmidt Telescope R plate taken by S. M. Hughes on June 22.5 UT. The object (mag 19) is located at R.A. = 16h12m16s.01, Decl. = -15 28'21".7 (equinox 1950.0), and is 3".6 west and 5".9 north of the galaxy's center. No image is evident at this location on J survey films. IAUC 5039 T LEONIS Patrick Schmeer, Federal Republic of Germany, reports that T Leo is in outburst. On 1990 June 24.89UT he estimated it at 10.7 but it was not recorded and fainter than 10.7 on June 19. Q1990/54 - alert cancelled. Observational error. Guy M Hurst