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IAUC 4453: N LMC; 1987A; PW Vul; 1987p

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                                                  Circular No. 4453
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

     R. H. McNaught, Siding Spring Observatory, reports that
Gordon Garradd, Tamworth, N.S.W., has discovered a nova in the LMC
on photographs taken on Sept. 21.  Magnitude estimates (hypered
2415 film, G = Garradd, M = McNaught): Sept. 15.53, [15 (G); 16.55,
[12.6 (M); 17.52, 9.7 (M); 17.53, 9.5 (G); 18.77, 11.0 (M); 19.60,
11.5 (M); 19.61, 11.6 (M); 21.54, 11.9 (G); 21.56, 11.9 (G); 21.77,
12.1 (M).  A Lumicon H alpha-filter observation by McNaught on Sept.
21.80 gave mag 11.0, and his visual estimates are Sept. 24.39,
13.2; 24.59, 13.3; 24.76, 13.5.  McNaught's precise measurement of
an Uppsala Schmidt exposure obtained on Sept. 24.8 gives for the
nova's position R.A. = 5h24m18s.26, Decl. = -70 03'21"3 (equinox 1950.0).

     D. Allen, Anglo-Australian Observatory; and P. Whitelock and
R. Catchpole, South African Astronomical Observatory, telex: "
Infrared photometry with the Radcliffe 1.9-m and A.A.O. 3.9-m
telescopes clearly shows two components.  One, identified with the
photosphere, is fading in line with the optical.  The other, seen
only beyond 3 microns, is more constant in luminosity but may be growing
redder.  A black-body fit to the radiation at 3.8 and 4.8 microns
suggests a temperature of about 700 K.  We believe this component to
be the infrared echo from a surrounding dust cloud, presumably
ejected during a former M-supergiant phase.  At 4.8 microns the echo
first appeared about 5 days after outburst and peaked in August.  It
now accounts for 80-percent of the emission at that wavelength,
making speckle observations of the echo possible."

     Visual magnitude estimates: June 28.94 UT, 14.8 (M. Verdenet,
Bourbon-Lancy, France); July 3.95, 14.6 (G. M. Hurst, Basingstoke,
England); 16.91, 14.9 (R. Monella, Covo, Italy); 28.92, 14.7
(Hurst); Aug. 12.9, 14.8 (Verdenet); 23.88, 14.4 (J. Ripero,
Madrid, Spain); 29.8, 14.5: (A. Mizser, Budapest, Hungary).

     Total visual magnitude estimates by A. Hale, Las Cruces, NM
(0.41-m refl.): Aug. 28.47, 12.5; Sept. 2.48, 12.5; 20.45, 12.1.

1987 September 24              (4453)              Brian G. Marsden

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