IAU Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8967: P/2008 Q2; eta Car

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 8966  SEARCH Read IAUC 8968

View IAUC 8967 in .dvi, .ps or .PDF format.
IAUC number

                                                  Circular No. 8967
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://www.cfa.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

COMET P/2008 Q2 (ORY)
     An apparently asteroidal object discovered by Michel Ory
(Delemont, Switzerland, on CCD images obtained with a 0.61-m f/3.9
reflector at Vicques; discovery observation tabulated below), which
was posted on the Minor Planet Center's 'NEOCP' webpage, has been
found by other CCD observers to be cometary.  A. Knoefel
(Schoenbrunn, Germany, 0.5-m reflector, Aug. 28.0 UT) reports an
apparent faint coma.  L. Buzzi (Varese, Italy, 0.60-m reflector,
Aug. 28.1) notes a 12" coma elongated to the southwest, adding that
his inspection of stacked astrographic images taken by R. Holmes
(Charleston, IL, U.S.A., Aug. 28.28) reveals a coma about 20" wide
that is elongated in p.a. 240 deg.  A. C. Gilmore and P. M.
Kilmartin remark that two stacked 120-s CCD frames taken with the
1.0-m f/7.7 reflector at Mt. John on Aug. 28.6 show a condensed,
circular coma of diameter 14" with no tail.

     2008 UT             R.A. (2000) Decl.       Mag.
     Aug. 27.09470    1 32 40.74   + 3 04 17.2   17.6

The available astrometry, the following preliminary elliptical
orbital elements, and an ephemeris appear on MPEC 2008-Q51.

     T = 2008 Oct. 23.018 TT          Peri. = 334.141
     e = 0.58310                      Node  =  59.478   2000.0
     q = 1.37046 AU                   Incl. =   2.814
       a =  3.28723 AU     n = 0.165370     P =   5.96 years

     A. Damineli -- on behalf of a large team monitoring eta Car
spectroscopicaly at the Observatories of Pico dos Dias (Brazil),
Casleo (Argentina), Las Campanas, and European Southern Observatory,
La Silla -- reports measurements in the He II 468.6-nm emission line.
The equivalent width was 0.009 nm at epochs 2007.3 and 2007.6, 0.012
nm at 2008.3, and 0.021 nm at 2008.6 -- repeating very well the past
cycle, as reported by Steiner and Damineli (2004, Ap.J. 612, L133).
The fact that the line-intensity curve follows the x-ray light curve
indicates that the He II emitting region is associated with the
wind-wind collision shock and not driven by a sudden shell ejection.
For related information, see also Damineli et al. 2008,
MNRAS 386, 2330.

                      (C) Copyright 2008 CBAT
2008 August 28                 (8967)            Daniel W. E. Green

Read IAUC 8966  SEARCH Read IAUC 8968

View IAUC 8967 in .dvi, .ps or .PDF format.

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

Valid HTML 4.01!