Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 9117: COMET P/2009 WJ_50 (LA SAGRA); COMETS C/2009 Y3 AND C/2009 Y4 (STEREO)

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 9116 SEARCH Read IAUC 9118

View IAUC 9117 in .dvi, .ps or .PDF format.
IAUC number 

                                                  Circular No. 9117
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  D. W. E. Green, Room 209; Department of
 Earth and Planetary Sciences; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
CBATIAU@EPS.HARVARD.EDU
URL http://www.cfa.harvard.edu/iau/cbat.html  ISSN 0081-0304


COMET P/2009 WJ_50 (LA SAGRA)
     An apparently asteroidal object discovered last November
(discovery observation tabulated below) on CCD images taken
remotely by the "La Sagra Sky Survey" (cf. IAUC 9078) was found on
Feb. 6 to show cometary appearance on WISE satellite images (cf.
IAUC 9115); A. Mainzer, Jet Propulsion Laboratory, reports that the
12- and 22-micron WISE images show an extended coma about 20" in
diameter with a tail extending at least 35" due east in thirteen
frames spanning 1.5 days.  Following a request by the Central
Bureau, M. T. Read obtained three CCD images with the Spacewatch
1.8-m reflector on Feb. 13.2 UT; analysis of Read's co-added images
by J. V. Scotti yields a coma of diameter 6" and total magnitude
about 22, with a broad fan-shaped extending about 0'.31 and
spanning p.a. 41-92 deg.  Also, W. H. Ryan and E. V. Ryan obtained
CCD images in poor transparency with the McDonald Observatory 2.4-m
reflector on Feb. 15.1 that yield red mag 20.1-20.3 with a faint
diffuseness toward p.a. about 50-80 deg.

     2009 UT             R.A. (2000) Decl.       Mag.
     Nov. 19.87722    3 04 49.35   + 8 15 38.8   18.7

The following improved elliptical orbital elements, residuals, and
an ephemeris appear on MPEC 2010-D01.

                    Epoch = 2010 Mar. 25.0 TT
     T = 2010 Mar. 12.4032 TT         Peri. =  27.1295
     e = 0.409774                     Node  =  74.9958  2000.0
     q = 1.791561 AU                  Incl. =  11.2759
       a =  3.035382 AU    n = 0.1863735    P =   5.29 years


COMETS C/2009 Y3 AND C/2009 Y4 (STEREO)
     Further to IAUC 9057, additional Kreutz sungrazers have been 
found on STEREO HI-1 website images (and subsequently on SOHO
website images).  K. Battams notes that C/2009 Y3 was found by M.
Uchina in SOHO C2 website data, where it peaked at mag about 7-7.5
and showed a 'double nucleus' that was not visible in HI-1 images.
C/2009 Y4 was bright (perhaps near mag 1 at peak), saturating SOHO
C3 and C2 images, where the tail was > 1 deg long; in HI-1 images,
the tail was several degrees long.

 Comet       2009 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2009 Y3   Dec. 19.184   12 50.3  - 9 58   HI-1   AW   2010-B28
 C/2009 Y4        31.128   13 05.8  -16 31   HI-1   AW   2010-B28

                      (C) Copyright 2010 CBAT
2010 February 16               (9117)            Daniel W. E. Green

Read IAUC 9116 SEARCH Read IAUC 9118

View IAUC 9117 in .dvi, .ps or .PDF format.

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

Valid HTML 4.01!