Central Bureau for Astronomical Telegrams
IAUC 8793: C/2006 P1
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 8794
.dvi,
.ps or
.PDF format.
Circular No. 8793
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/2006 P1 (McNAUGHT)
K. Battams, Interferometrics, Inc., and Naval Research
Laboratory, reports that images of comet C/2006 P1 obtained on Jan.
11 with the SECCHI/HI-1B instrument on the NASA STEREO-B (Behind)
spacecraft are available at the following website URL:
http://ares.nrl.navy.mil/sungrazer/index.php?p=latest_news. The
images show a curved, striated dust tail some 7 degrees long, the
bright coma being heavily saturated due to its brightness.
J. N. Marcus writes that forward-scattering brightness
enhancement should peak in C/2006 P1, as viewed from the earth, on
Jan. 14 at a level approximately 2.3 magnitudes brighter than what
would be predicted by a standard power law (model details in Marcus
2007, ICQ, submitted).
Selected visual total-magnitude, coma-diameter, and tail-
length/p.a. estimates made with the comet at low altitude (all
magnitudes were corrected by the observers for atmospheric
extinction) and in nautical or civil twilight unless otherwise
noted: 2006 Dec. 29.28 UT, 3.9, 1'.5, -- (B. H. Granslo,
Fjellhamar, Norway, 0.10-m refractor); 2007 Jan. 2.30, 2.7, 1'.5,
0.1 deg in p.a. 0 deg (J. J. Gonzalez, Leon, Spain, 25x100
binoculars); 3.28, 1.5, 1'.7, 0.2 deg (H. Dahle, Fjellhamar,
Norway, 9x63 binoculars); 4.64, 1.0:, --, -- (Dahle, Blindern/Oslo,
Norway, naked eye); 5.72, -0.5:, --, -- (D. Moore, Dublin, Ireland,
naked eye); 6.28, 0.2:, 1', 1 deg in p.a. 0 deg (Granslo, Tryvann/
Oslo, Norway, 7x50 binoc.); 7.30, 0.0:, 1', 0.4 deg (N. Biver,
Meudon, France, 7x50 binoc.); 7.48, -0.5:, about 1', < 1 deg (D. W.
E. Green, Rowley, MA, U.S.A., 7x35 binoc.); 8.25, -1.2:, 3', 0.5
deg (K. Hornoch, Vranov, Czech Republic, naked eye); 8.65, -0.8:,
--, 1.5 deg (O. Skilbrei, Honefoss, Norway, naked eye); 8.93, -1.5:,
about 1', -- (J. E. Bortle, Stormville, NY, U.S.A., naked eye);
9.68, -2.0, --, -- (W. Hasubick, Buchloe, Germany, naked eye); 9.71,
-2.2:, 1', 1.5 deg (Biver, naked eye); 9.98, -2.9:, --, short (J. N.
Marcus, St. Louis, MO, U.S.A., naked eye); 10.30, -2.2:, --, 1.0
deg in p.a. 15 deg (T. Karhula, Vaesteraas, Sweden, naked eye);
10.34, -2.2:, --, 0.3 deg in p.a. 15 deg (S. Yoshida, Toride,
Ibaraki, Japan, 10x70 refractor); 10.66, -2.7:, 5', 2 deg in p.a.
25 deg (K. Hornoch, Krasensko, Czech Rep., 10x50 binoculars); 10.68,
-3.2, 2', 2 deg (T. Scarmato, Calabria, Italy, 7x50 binoc.); 10.83,
-2.5:, --, short (R. A. Keen, Mt. Thorodin, CO, U.S.A., 7.6-cm
reflector; broad daylight; comparison with Venus); 10.92, -2.5:,
about 1', 1 deg (Bortle); 10.95, -2.9:, 1', 1.6 deg in p.a. 15 deg
(P. Creed, New London, OH, U.S.A., 10x50 binoc.); 11.34, -2.8,
about 3', 1 deg (Y. Nagai, Gunma, Japan, 7x35 binoc.); 11.68, -3.5,
3', about 2 deg (Scarmato, naked eye); 11.75, -3.5:, --, 1 deg (A.
Pereira, Cabo da Roca, Portugal, naked eye).
(C) Copyright 2007 CBAT
2007 January 11 (8793) Daniel W. E. Green
Read IAUC 8794
.dvi,
.ps or
.PDF format.
Our Web policy. Index to the CBAT/MPC/ICQ pages.
