Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 6886: 1998bn; SAX J1808.4-3658 = XTE J1808-369; 1998 H1

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 6885 SEARCH Read IAUC 6887

View IAUC 6886 in .dvi or .ps format.
IAUC number 

                                                 Circular No. 6886
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html
Phone 617-495-7244/7440/7444 (for emergency use only)


SUPERNOVA 1998bn IN NGC 4462
     W. D. Li, M. Modjaz, R. R. Treffers, and A. V. Filippenko,
University of California at Berkeley, report the discovery of an
apparent supernova during the course of the Lick Observatory
Supernova Search (cf. IAUC 6627) with the 0.8-m Katzman Automatic
Imaging Telescope.  SN 1998bn was found and confirmed on unfiltered
CCD images obtained on Apr. 17.3 (mag about 17.4) and 27.3 UT (mag
about 13.7), respectively.  The object is located at R.A. =
12h29m18s.88, Decl. = -23o09'49".2 (equinox 2000.0), which is about
32".3 west and 9".7 north of the nucleus of NGC 4462.  The new star
already appeared in the template image obtained on Apr. 17.3, and
brightened about 3.7 mag in 10 days.  The Digital Sky Survey does
not show any star at the position of SN 1998bn.


SAX J1808.4-3658 = XTE J1808-369
     A. B. Giles, K. M. Hill, and J. G. Greenhill, Physics
Department, University of Tasmania, report:  "We have CCD
observations of SAX J1808.4-3658 that appear to confirm the optical
candidate proposed by Roche et al. on IAUC 6885.  A set of 23
V-band images covering the about 2-hr x-ray binary period of
Chakrabarty and Morgan (IAUC 6877) was obtained with the Mt.
Canopus 1-m telescope during Apr. 22.70-23.79 UT.  There is a
roughly-sinusoidal modulation of 0.12 mag peak-to-peak, with a
maximum at about Apr. 22.75.  A set of five V images spanning about
0.5 hr obtained on Apr. 18.70 shows the object to be brighter by
about 0.1 mag, assuming that the sine modulation is persistent.
The intensity decrease between the two data sets provides further
evidence for the proposed identification."


COMET 1998 H1
     A. Miyamoto and T. Oribe, Saji Observatory, report (via S.
Nakano, Sumoto) a coma diameter of 12" and a tail 3' long in p.a.
190 deg on CCD images obtained on Apr. 26.774 UT with a 1.03-m
reflector.
     Total visual magnitude and coma-diameter estimates:  Apr.
26.97 UT, 10.6, 3' (K. Hornoch, Lelekovice, Czech Republic, 0.35-m
reflector); 26.99, 10.2, 6' (M. Meyer, Frauenstein, Germany, 20x100
binoculars).
     Corrigenda to IAUC 6883.  Line 13, for  23.016  read  23.16.
Fourth line from the bottom, for  p.a. 155 deg  read  p.a. 205 deg

                      (C) Copyright 1998 CBAT
1998 April 27                  (6886)            Daniel W. E. Green

Read IAUC 6885 SEARCH Read IAUC 6887

View IAUC 6886 in .dvi or .ps format.

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

Valid HTML 4.01!