Central Bureau for Astronomical Telegrams
IAUC 7625: C/2001 J1; C/2001 A2; 2001bf
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 7626
.dvi or
.ps format.
Circular No. 7625
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)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)
COMET C/2001 J1 (NEAT)
MPEC 2001-J34 contains 40 astrometric observations May 11-15 and
parabolic orbital elements (T = 2001 Mar. 19, q = 1.00 AU, Peri. = 279 deg,
Node = 198 deg, Incl. = 11 deg, equinox 2000.0) computed from 26 of them.
The orbit is still very indeterminate, and it is not clear whether or not
the comet is of short period.
COMET C/2001 A2 (LINEAR)
J. Broughton, Reedy Creek, Queensland, writes that his CCD observations
(0.25-m f/6.6 Schmidt-Cassegrain) on May 9.3 UT showed the brighter (western)
component at m2 = 14.7, with the secondary, 0.3 mag fainter, perhaps 5"
distant in p.a. 100 deg, although some elongation of the secondary could make
the separation as much as 7". On May 10.3 the appearance was similar. On May
11.3 the western component had brightened to m2 = 13.2, and the eastern
component had virtually disappeared. On May 12.4 the western component had
faded to m2 about 14.0, while the secondary was then perhaps 2 mag fainter,
8".5 away in p.a. 100 deg.
Using the absolute astrometry for Apr. 30 (see IAUC 7616) and May 9
given on MPC 42656 (where the western primary is labeled B and the eastern
secondary is labeled A), Z. Sekanina, Jet Propulsion Laboratory, obtained
a separation time of Mar. 17 +/- 12 and an acceleration of 7.1 +/- 2.4 (in
units of 10**-5 solar gravity).
Total visual magnitude estimates by A. Pearce, Nedlands, Western
Australia (20 x 80 binoculars): May 9.48 UT, 6.2; 11.44, 5.3; 13.49, 5.2;
14.49, 5.4; 15.49, 5.4.
SUPERNOVA 2001bf IN MCG +04-42-22
H. Kawakita and K. Kinugasa, Gunma Astronomical Observatory; and H.
Yamaoka, Kyushu University, write: "Despite the low-S/N ratio, a
low-resolution spectrum of SN 2001bf taken with the Gunma 0.65-m telescope
(+ GCS spectrograph) on May 11.61 UT clearly shows a deep and broad Si II
absorption feature around 610 nm on a rather blue continuum, indicating that
this is a type Ia supernova shortly before maximum light. Other
broad absorption features typical of type Ia events are also seen."
Visual magnitude estimates by J. D. West, Mulvane, KS: May 7.44 UT, 14.6;
8.44, 14.4. An unfiltered CCD measurement, also by West, on May 14.438
gave R = 14.5 +/- 0.2.
(C) Copyright 2001 CBAT
2001 May 15 (7625) Brian G. Marsden
Read IAUC 7626
.dvi or
.ps format.
Our Web policy. Index to the CBAT/MPC/ICQ pages.
