Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8768: C/2006 U5; P/2006 S4

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 8767 SEARCH Read IAUC 8769

View IAUC 8768 in .dvi, .ps or .PDF format.
IAUC number 

                                                  Circular No. 8768
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 U5 (CHRISTENSEN)
     E. J. Christensen, Lunar and Planetary Laboratory, University
of Arizona, reports his discovery of a comet with a 15" coma and a
short, fan-shaped tail spanning p.a. 260-290 deg on four co-added
60-s images taken with the 0.68-m Schmidt telescope in the course
of the Catalina Sky Survey (discovery observation tabulated below).
Following posting on the Minor Planet Center's NEOCP webpage,
numerous other observers have commented that their CCD astrometric
observations also show this object to be cometary in appearance.
G. Hug (Eskridge, KS, 0.7-m reflector) found a faint, broad tail
centered at p.a. about 260 deg on his images from Oct. 28.4 UT.  G.
Sostero and E. Guido (Remanzacco, Italy, 0.45-m f/4.4 reflector)
write that their frames from Oct. 29.1 show a diffuse coma 20" in
diameter with total mag 17.8 and a broad tail 30" long toward p.a.
315 deg.  B. L. Stevens (Las Cruces, NM, 0.3-m Schmidt-Cassegrain
reflector) reports that his images from Oct. 29.4 show a 7" coma
and a 27"-long tail spanning 36 deg of p.a., centered at p.a. 267
deg.  J. Young (Table Mountain Observatory, 0.61-m f/16 Cassegrain
reflector) notes that his images from Oct. 29.4 show a diffuse
coma of diameter 6" with little central condensation and a very
broad, poorly defined, fan-shaped tail directed toward a central
p.a. of 265 deg.

     2006 UT             R.A. (2000) Decl.       Mag.
     Oct. 27.39343    6 42 08.03   +27 25 28.4   18.0

The available astrometry, the following preliminary parabolic
orbital elements, and an ephemeris appear on MPEC 2006-U69.

     T = 2006 Aug. 31.906 TT          Peri. =  43.150
                                      Node  =  17.276   2000.0
     q = 2.56243 AU                   Incl. =   3.840


COMET P/2006 S4 (CHRISTENSEN)
     Elliptical orbital elements (cf. IAUC 8753) from MPEC 2006-U29:

     T = 2006 June  1.593 TT          Peri. = 305.689
     e = 0.50816                      Node  =  36.142   2000.0
     q = 3.06767 AU                   Incl. =  39.622
       a =  6.23713 AU     n = 0.063274     P =  15.58 years

                      (C) Copyright 2006 CBAT
2006 October 29                (8768)            Daniel W. E. Green

Read IAUC 8767 SEARCH Read IAUC 8769

View IAUC 8768 in .dvi, .ps or .PDF format.

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

Valid HTML 4.01!