Central Bureau for Astronomical Telegrams
IAUC 4379: NO SN IN NGC 5363; 1987D; NGC 4418
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Circular No. 4379
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
NO SUPERNOVA IN NGC 5363
H. Kosai, Tokyo Astronomical Observatory, and R. H. McNaught,
Siding Spring Observatory, both note that the object reported as a
SN on IAUC 4378 is a foreground star (V = 12.1). R. Evans,
Hazelbrook, N.S.W., found nothing new in NGC 5363 on Apr. 2 and 20.
SUPERNOVA 1987D IN MCG +0-32-01
M. A. Strauss, Astronomy Department, University of California
at Berkeley, communicates: "Spectroscopy was obtained of SN 1987D
with the Lick Observatory Nickel 1.02-m telescope, in the spectral
regions 430-600 and 620-760 nm, on Apr. 27 UT. The absence of H(alpha)
emission and the presence of strong absorption at 615.0 nm identify
the SN as type Ia. (Though 615.0 nm is not covered by the observations,
we observed a large drop in the red spectrum to 620.0 nm.)
Comparison with spectra of other type-Ia supernovae suggests that
these observations were performed 2 +/- 1 week after maximum,
consistent with the date of discovery, Apr. 21, and the fact that the
supernova was not present on Apr. 2."
NGC 4418
L. Bottinelli, L. Gouguenheim, A. M. le Squeren, and J. M. Martin,
Observatoire de Paris, Meudon; M. Dennefeld, Institut d'Astrophysique;
and G. Paturel, Observatoire de Lyon, telex: "We have detected with
the Nancay radio telescope a new megamaser in the highly-obscured
(visual extinction = 55 to 120 mag according to Roche et al. 1986,
M.N.R.A.S. 218, 19P), active-nuclei galaxy NGC 4418. The 1667-MHz
main-line isotropic luminosity is 1.4 solar luminosities (taking
H = 75 km/s/Mpc), or 3 orders of magnitude lower than in the
most luminous known megamaser, IRAS 1720-0014 (IAUC 4106). The
infrared luminosity has also the lowest value among the megamasers:
it is 30 and 24 times less luminous in the infrared, respectively,
than the two most luminous megamasers, Markarian 231 and IRAS
1720-0014. The 1667- to 1665-MHz main-lines peak ratio = 2.6."
COMET WILSON (1986l)
Further total visual magnitude estimates: Apr. 25.70 UT, 5.6
(G. Garradd, Tamworth, N.S.W., 7 x 50 binoculars); 29.42, 5.5 (D.
A. J. Seargent, The Entrance, N.S.W., 2.5 x 25 binoculars).
1987 April 30 (4379) Daniel W. E. Green
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