Circular No. 4048 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444 PERIODIC COMET ASHBROOK-JACKSON (1985a) This comet has been recovered by A. C. Gilmore and P. M. Kilmartin at the Mount John University Observatory, as follows: 1985 UT R.A. (1950.0) Decl. m2 Mar. 20.66322 19 15 42.09 -34 23 09.4 18 20.70766 19 15 45.86 -34 23 11.0 The object is of stellar appearance and the position in very close agreement with the prediction by E. I. Kazimirchak-Polonskaya (1982, Trudy Inst. Teor. Astron. 18, 91). UNUSUAL OBJECT IN NGC 4618 J. Gibson, Jet Propulsion Laboratory, has measured the following precise position of this object (IAUC 4042) from an plate taken on Mar. 17 by J. Schombert with the 1.2-m Palomar Schmidt telescope: R.A. = 12h39m09s56, Decl. = +41deg25'32"7 (equinox 1950.0). A. V. Filippenko, University of California at Berkeley; and W. L. W. Sargent, California Institute of Technology, confirm that the object is a peculiar supernova. It is visible on photographic plates taken by E. A. Harlan at the Lick Observatory on Mar. 16, whereas similar plates obtained on 1914 May 26 show only a bright H II region at the same location. Spectrophotometry on 1985 Mar. 17 and 19 with the Shane 3-m telescope reveals several prominent, broad emission lines in spectral regions not observed previously. Possible identifications are K I 404.6, [N I] 519.9, [O II] 732.5 and O I 777.4 nm. Note that the FWZI of the strongest line ([O I] 630.0 nm) is over 25 000 km/s, not 15 000 km/s as stated on IAUC 4042. This type of supernova may be the progenitor of certain oxygen-rich remnants such as Cas A and the one in NGC 4449. RS OPHIUCHI Visual magnitude estimates: Feb. 16.25 UT, 7.6 (K. Medway, Southampton, England); 19.54, 8.5 (L. Cook, Concord, CA); 21.42, 8.3 (J. Bortle, Stormville, NY); 23.75, 8.6 (R. H. McNaught, Coonabarabran, N.S.W); 25.76, 8.8 (McNaught); 28.34, 9.1 (Bortle); Mar. 4.22, 8.8 (G. M. Hurst, Basingstoke, England); 4.22, 9.2 (S. Lubbock, Bridgend, Wales); 5.23, 9.3 (Medway); 6.22, 9.4 (Medway). 1985 March 21 (4048) Brian G. Marsden
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