Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8351: COMET C/2001 Q4 (NEAT); C/2003 V2, V3, V4, V5

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 8350  SEARCH Read IAUC 8352

View IAUC 8351 in .dvi or .ps format.
IAUC number

                                                  Circular No. 8351
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  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

COMET C/2001 Q4 (NEAT)
     S. M. Brafford, University of Dayton; M. L. Sitko, University
of Cincinnati; and R. W. Russell and D. L. Kim, The Aerospace
Corporation, report 3-13-micron spectrophotometry of comet C/2001
Q4, obtained on May 31.2 UT with the Mt. Lemmon 1.5-m University of
Minnesota telescope (+ Aerospace Broadband Array Spectrograph
System; 8".5 aperture; 49" chop throw; integration times 10 min on
the comet and 20 min on the reference star, alpha Lyr):  "A smooth
comet continuum was seen to rise from 3.5 to 8.4 microns, beyond
which a strong silicate emission band was observed.  An underlying
blackbody continuum with a temperature of about 345 +/- 10 K was
fit to the continuum flux at 5, 8.4, and 12 microns.  This grain
temperature is about 24 percent higher than that of an equilibrium
blackbody at the heliocentric distance of the comet, and higher
than that observed on May 14.1 (IAUC 8342) using the same
instrument and telescope when the comet was closer to the sun.
Structure is seen in the silicate feature, including emission peaks
at 10.5 and 11.2 microns.  The silicate-feature-to-continuum ratio
was about 1.43 +/- 0.04, lower than that reported on May 14.2.  No
scattered solar flux was detected at the shorter wavelengths after
subtracting the thermal continuum.  With our aperture, the comet
has the following narrowband (about 0.25 micron) magnitudes and
combined random errors (due to calibration star and comet, as well
as variations due to the presence of real spectral structure):
[3.7 microns] = 6.8 +/- 0.3, [4.7 microns] = 4.60 +/- 0.11, [5
microns] = 4.27 +/- 0.06, [8 microns] = 1.71 +/- 0.06, [10.5
microns] = -0.54 +/- 0.02, and [12 microns] = -0.49 +/- 0.03 (the
stated errors are standard deviations of the mean)."

COMETS C/2003 V2, V3, V4, V5 (SOHO)
     Further to IAUC 8348, K. Battams reports measurements for
additional Kreutz sungrazing comets found on SOHO website C2 images
(by R. Kracht, C/2003 V2; M. Boschat, C/2003 V3, V4, and V5);
C/2003 V3 and V5 were also visible on C3 images.  The reductions by
R. Kisala and orbital elements by B. G. Marsden appear on MPEC

    Comet         2003 UT          R.A. (2000) Decl.
    C/2003 V2     Nov.  1.896      14 21.9   -15 35
    C/2003 V3           3.513      14 19.5   -17 14
    C/2003 V4           4.938      14 33.7   -16 43
    C/2003 V5           5.388      14 23.2   -20 18

                      (C) Copyright 2004 CBAT
2004 June 11                   (8351)            Daniel W. E. Green

Read IAUC 8350  SEARCH Read IAUC 8352

View IAUC 8351 in .dvi or .ps format.

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

Valid HTML 4.01!