Circular No. 4561 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 SUPERNOVA 1988H IN NGC 5878 A. V. Filippenko and G. Basri, University of California at Berkeley, report that spectra (range 390-700 nm, resolution 1-2 nm) obtained by Basri on Mar. 8 UT with a CCD spectrograph on the 3-m Shane reflector at Lick Observatory show that the new object in NGC 5878 (IAUC 4560) is a type-II supernova, probably a few weeks past maximum brightness. Strong, broad (FWHM about 8000 km/s) H-alpha emission is present, as is a blueshifted H-alpha absorption trough. 4U 0115+63 G. Henson and J. Imamura, Pine Mountain Observatory, University of Oregon, write: "The optical counterpart of the transient x- ray source 4U 0115+63 has brightened from V = 14.3 +/- 0.1 on 1987 Nov. 22 to V = 13.5 +/- 0.1 on 1988 Feb. 27. Such an increase in brightness usually precedes an x-ray outburst from the object (IAUC 4350); therefore, x-ray observations are encouraged." SUPERNOVA 1988G IN ANONYMOUS GALAXY Corrigendum. On IAUC 4559, line 3, for 6".7 east read 6".7 west SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD A. Crotts, McDonald Observatory, University of Texas, Austin, telexes: "I have discovered two features caused by the optical- wavelength light echo from SN 1987A. Observations on Mar. 3-7 with a coronagraph on the Carnegie Institution's 1.02-m Swope telescope revealed two arcs centered on SN 1987A with position angles -90 deg to +75 deg and -60 to +90 deg, and radii of 47" and 32", respectively. The arcs are seen where circles of these radii intersect regions of dense H-alpha emission, even though the features are not particularly strong in H-alpha. No such structures are seen in pre-explosion photographs, nor did they appear when the coronagraph was used to observe bright stars with the same setup and with the telescope at similar declinations and air masses. The inner and outer arcs lie in front of SN 1987A by 440 and 950 light years, and should be moving superluminally from the center at 1".6/month and 2".4/month, respectively. The eastern-most portion of the outer arc may fade in several months as it passes into regions of lower density." 1988 March 9 (4561) Daniel W. E. Green
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