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IAUC 4561: 1988H; 4U 0115+63; 1988G; 1987A

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IAUC number

                                                  Circular No. 4561
Central Bureau for Astronomical Telegrams
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

     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."

Corrigendum.  On IAUC 4559, line 3, for  6".7 east  read  6".7 west

     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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