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IAUC 4574: DO Dra; 1987A; N LMC; 1987L

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IAUC number 

                                                  Circular No. 4574
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


DO DRACONIS
     J. A. Mattei, AAVSO, reports that this cataclysmic variable
has undergone another outburst, as indicated by the following visual
magnitude estimates: Mar. 30.14 UT, 11.4 (G. Dyck, N. Dartmouth,
MA); 30.84, 10.4 (S. Lubbock, Bridgend, Mid-Glamorgan, Wales).  The
last reported outburst was in 1985 (cf. IAUC 4143).


SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD
     H. Moseley, E. Dwek, W. Glaccum, J. Graham, R. Loewenstein,
and R. Silverberg report:  "New observations of SN 1987A in the 16-
30-micron spectral range were made using the Goddard Space Flight
Center's 24-channel cryogenic grating spectrometer aboard the Kuiper
Airborne Observatory on Mar. 23 and 26.  The spectrum is dominated
by three strong [Fe II] lines, the ground-state fine-structure line
at 25.98 microns, and the two fine-structure lines arising from excited
electronic states at 17.93 and 24.52 microns.  There is evidence for
detection of the ground-state line of [Fe I] at 24.05 microns, as well.
The line strengths are similar to their 1987 Nov. values, except
that the excited state lines in [Fe II] are stronger.  Comparison
with Nov. observations made with the same instrument shows dramatic
changes in other aspects of the spectrum.  The line at 18.8 microns,
which was strong in the Nov. measurements, has effectively disappeared;
the reduction in line strength supports its identification
with [Co II] rather than [S III], the alternate possibility.  The H
recombination lines in this spectral region (strong in Nov.) have
also disappeared.  The continuum, attributed to free-free emission,
has dropped about a factor of three since Nov."


NOVA IN THE LARGE MAGELLANIC CLOUD
     Visual magnitude estimates (cf. IAUC 4569):  Mar. 23.46 UT,
11.0 (B. Tregaskis, Mt. Eliza, Victoria); 24.44, 11.4 (G. Garradd,
Tamworth, N.S.W.); 25.40, 11.3 (R. H. McNaught, Siding Spring
Observatory); 27.42, 11.6 (P. Williams, Heathcote, N.S.W.); 28.46,
11.2 (D. Seargent, The Entrance, N.S.W.); 29.44, 11.6 (Williams).


SUPERNOVA 1987L IN NGC 2336
     Photographic magnitude estimate by R. Royer, Wrightwood, CA:
Jan. 22, 18.0-18.2.


1988 March 30                  (4574)            Daniel W. E. Green

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