Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 7041: 1998em; 1ES 2005-489; N Sco 1998

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 7040  SEARCH Read IAUC 7042

View IAUC 7041 in .dvi or .ps format.
IAUC number

                                                 Circular No. 7041
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://cfa-www.harvard.edu/iau/cbat.html
Phone 617-495-7244/7440/7444 (for emergency use only)

SUPERNOVA 1998em IN IC 4837A
     J. Maza, Department of Astronomy, University of Chile, reports
the discovery of a supernova (B about 16.5) by Roberto Antezana on
a T-Max 400 film taken by L. E. Gonzalez with the Maksutov
telescope at Cerro El Roble on Oct. 26.96 UT.  SN 1998em is located
at R.A. = 19h15m12s.69, Decl. = -54o06'49".7 (equinox 2000.0),
which is 26" west and 67" north of the spiral galaxy IC 4837A.  The
new object is not present on a film taken on Oct. 13.96 (B > 19).
SN 1998em was confirmed on direct CCD images taken by I. Perez on
Oct. 27.95 using the 1.0-m Swope telescope at Las Campanas
Observatory.  A spectrum was obtained by W. Kunkel, Carnegie
Institution of Washington (CIW), using the du Pont telescope (+
Modular Spectrograph) at Las Campanas.  M. Phillips, CIW, reports:
"The spectrum of the supernova exhibits strong, broad Si II
635.5-nm absorption consistent with a type-Ia event at maximum, or
perhaps a few days before.  Narrow Galactic interstellar Na I D
lines with a combined equivalent width of 0.054 nm are observed
near zero velocity.  A second set of Na I D absorption lines with
an equivalent width of 0.11 nm and presumably due to gas in the
host galaxy IC 4837A is present at a redshift of 0.0091."

1ES 2005-489
     R. Remillard reports for the ASM instrument teams at the
Massachusetts Insitute of Technology and Goddard Space Flight
Center: "The RXTE All Sky Monitor has detected increased x-ray flux
from the BL Lac object 1ES 2005-489 = PKS 2005-489 (R.A. =
20h09m25s.39, Decl. = -48o49'53".8, equinox 2000.0).  During the
interval Oct. 11-28, the flux has been in the range of 4 to 10
mCrab at 2-12 keV, which is a factor of 2-3 above its typical
intensity during 1996-1998.  Observations at other wavelengths are
strongly encouraged."

     W. Liller, Vina del Mar, Chile, reports the following
magnitudes for N Sco 1998 as measured with a broadband-V system
(CCD + minus-infrared filter).  Note that the first magnitude has
been revised slightly from what appeared on IAUC 7037:  Oct.
23.0029 UT, 7.71; 23.9983, 8.08; 25.0006, 8.34; 25.9993, 8.45.
     Additional visual magnitude estimates by W. G. Dillon,
Missouri City, TX:  Oct. 25.05 UT, 9.2; 26.03, 9.4; 27.03, 9.6.

                      (C) Copyright 1998 CBAT
1998 October 28                (7041)            Daniel W. E. Green

Read IAUC 7040  SEARCH Read IAUC 7042

View IAUC 7041 in .dvi or .ps format.

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

Valid HTML 4.01!