[IAUC] IAUC 8922: 2006 SF_369; (119067) 2001 KP_76, (160091) 2000 OL_67; C/2007 T1 [25139-2008/05-R1]

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                                                  Circular No. 8922
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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2006 SF_369
     K. S. Noll and S. D. Kern, Space Telescope Science Institute
(STScI); W. M. Grundy, Lowell Observatory; H. F. Levison, Southwest
Research Institute; and E. A. Barker, STScI, report that the 1:3
Neptune-librating transneptunian object 2006 SF_369 (cf. MPEC
2006-U61) is a binary.  One 260-s exposure was made at each of four
dithered positions on the detector during 2007 Nov. 13.3563-13.3868
UT with the Planetary Camera of the Wide Field Planetary Camera 2
on the Hubble Space Telescope (HST), using the F606W filter (wide
V); these exposures show two components for 2006 SF_369 that were
separated by an angular distance of 0".109 +/- 0".003 and were
nearly equal in brightness (differing by < 0.1 mag).  The fainter
component was located at -0".019 +/- 0".002 in R.A. and -0".107 +/-
0".002 in Decl. from the brighter component.   One of three objects
known or suspected to be in 1:3 resonance with Neptune [the others
being (136120) 2003 LG_7 (MPEC 2005-L33) and 2005 EO_297 (Deep
Ecliptic Survey integration)] and which have been observed with
HST, 2006 SF_369 is the only detected binary.


(119067) 2001 KP_76 AND (160091) 2000 OL_67
     F. Marchis and M. Baek, Carl Sagan Center, SETI Institute; and
J. Berthier, P. Descamps, and F. Vachier, Institut de Mecanique
Celeste et de Calcul des Ephemerides, Paris; jointly with K. S.
Noll and S. D. Kern, Space Telescope Science Institute; and W. M.
Grundy, Lowell Observatory, report on companions to the cubewanos
(119067) 2001 KP_76 [cf. MPEC 2001-M60, MPO 88168] and (160091)
2000 OL_67 [cf. MPEC 2000-T41, MPO 121405].  Observations of
(119067) were made during 2007 May 8.576-8.597 UT with the HST as
noted above; the processed image (the result of four dithered
positions on the detector, as described above) shows two components
separated by 0".9429 in p.a. 276 deg and having a brightness
difference of only 0.1 magnitude.  A companion was detected around
(160091) in HST observations taken as above between 2007 June
26.514 and 26.487; a brightness difference of 0.6 magnitude is
clearly visible for the two components in the processed image
(processed as above), and its separation is 0".9426 in p.a. 277
deg, corresponding to a projected distance of 7800 km.


COMET C/2007 T1 (McNAUGHT)
     Total visual magnitude estimates by D. A. J. Seargent, Cowra,
N.S.W. (25x100 binoculars):  2007 Nov. 10.42 UT, 9.7; 2008 Jan.
8.45, 8.7; 11.48, 8.3; Feb. 7.48, 8.7; 9.47, 8.8.

                      (C) Copyright 2008 CBAT
2008 February 19               (8922)            Daniel W. E. Green