Central Bureau for Astronomical Telegrams
IAUC 4317: 1987A
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Circular No. 4317
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 1987A IN THE LARGE MAGELLANIC CLOUD
D. Herald, Canberra, provides the following precise position
from an exposure on Feb. 25.42 UT: R.A. = 5h35m50s.11, -69 17'58".5
(equinox 1950.0).
R. H. McNaught, Siding Spring Observatory, reports that M.
Morel, Rankin Park, N.S.W., notes that the star implied on IAUC
4316 as associated with the possible progenitor of the supernova
is CPD -69 402 (mag 10.2) = Sanduleak -69 202. Sanduleak (1969,
Contr. CTIO No. 89) indicated that it is an LMC member and provided
a finder chart. Photometry and spectroscopy by Rousseau et
al. (1978, A. Ap. Supp. Ser. 31, 243) give V = 12.24, B-V = +0.04,
U-B = -0.65, spectrum B3 I. For another LMC member 3' north, CPD
-69 400 (mag 10.2) = Sanduleak -69 203, Rousseau et al. give V =
12.29, suggesting no secular variation since the CPD was compiled.
B. Madore, Las Campanas Observatory, reports that photometry
by I. Shelton and J. Claria on Feb. 25.219 UT gave V = 4.63, B-V =
+0.21, U-B = -0.63. Spectra obtained by A. Davidsen, R. Kimble
and M. Gregg with the 2.5-m Dupont reflector beginning on Feb. 25.0
UT show a strong continuum with very broad H alpha, beta and gamma
absorption. The minima of these features are blueshifted by about 15000
km/s. The full width of the H beta feature is about +/- 7500 km/s. There
is also a similarly strong and broad absorption near 589 nm (rest
frame) that may be He I 588 nm and/or the Na D lines. The continuum
distribution is similar to that of the A1 V star theta Vir. They
suggest that the supernova may be of type II.
G. Sonneborn, IUE Science Operations Center, Goddard Space
Flight Center, and R. Kirshner, Center for Astrophysics, report:
"The LMC supernova was observed with the International ultraviolet
Explorer satellite from Goddard Space Flight Center during Feb.
24.8-25.1 UT. The estimated V magnitude from the IUE fine-error-
sensor varied between 5.0 and 4.8. Both low- and high-dispersion
spectra were obtained with the SWP (120-200 nm) and LWP (200-320
nm) cameras. The ultraviolet spectrum is featureless and quite
strong longward of 130 nm. An absorption trough > 10 nm wide and
centered near 171 nm was detected. The high-dispersion spectra
contain numerous strong interstellar/galactic halo absorption
lines. At least six sharp absorption components were detected in
the Mg I 285.2 nm line. The supernova will continue to be
monitored frequently by the IUE from GSFC and Vilspa."
1987 February 25 (4317) Brian G. Marsden
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