Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 4564: 1987A; IHW DEADLINE; 1986h; 1987f1

The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).

Read IAUC 4563 SEARCH Read IAUC 4565
IAUC number 

                                                  Circular No. 4564
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
     M. Rosa, European Southern Observatory, Garching, writes:  "The
light echoes referred to on IAUC 4561 have been found on images
obtained with the ESO 3.6-m telescope (+ EFOSC in coronographic mode)
at La Silla on Feb. 13.  A narrow band image centered at 470 nm
(width 6 nm) shows two complete rings.  Brightness and width are
greater in the northeast and northwest quadrants and less towards
the south.  The radii are 31" and 52" (uncertainty about 1" due to
the width, 5"-10", and diffuseness of the rings).  The outer ring
has a slightly larger radius to the south (53"-54").  Comparison
with exposures obtained Mar. 16 with the same equipment in several
wavelength bands by C. Gouiffes (ESO, La Silla) and M. Ruiz (
University of Chile) demonstrates clearly that the ring diameters are
expanding.  Differences in radii of the inner and outer rings are
1" and 3", albeit with large uncertainty."
     Visual magnitudes by A. C. Beresford, Adelaide, S. Australia:
Mar. 11.54 UT, 7.0; 14.44, 7.2; 15.45, 7.2; 16.47, 7.0; 17.46, 7.2.


INTERNATIONAL HALLEY WATCH DEADLINE
     R. Newburn and J. Rahe, International Halley Watch, Jet
Propulsion Laboratory, note that those who have not yet submitted data
for the IHW archive must do so by 1989 Jan. 1.  Submitted data will
remain protected until archive publication in late 1989, and those
submitting data will receive a free copy of the entire archive.


PERIODIC COMET SCHWASSMANN-WACHMANN 2 (1986h)
     Further total visual magnitude estimates:  Feb. 11.39 UT, 13.0
(E. Jacobson, Evansville, MN, 0.25-m reflector); 15.48, 13.8 (A.
Hale, Las Cruces, NM, 0.41-m reflector); 17.45, 13.1 (Jacobson);
28.52, 13.8 (Hale).


COMET FURUYAMA (1987f1)
     Further total visual magnitude estimates (cf. IAUC 4545): Feb.
13.15 UT, 9.9 (C. S. Morris, Whitaker Peak, CA, 0.26-m reflector);
14.12, 9.7 (A. Hale, Las Cruces, NM, 0.41-m reflector); 15.76, 10.7
(A. Boattini, Piazzano, Italy, 0.40-m reflector); 16.14, 9.8
(Morris); 21.10, 9.9 (Hale).


1988 March 17                  (4564)            Daniel W. E. Green

Read IAUC 4563 SEARCH Read IAUC 4565

Our Web policy. Index to the CBAT/MPC/ICQ pages.

Valid HTML 4.01!