Central Bureau for Astronomical Telegrams
IAUC 8194: Sats OF URANUS; C/2002 VQ_94
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 8195
.dvi or
.ps format.
Circular No. 8194
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)
SATELLITES OF URANUS
M. R. Showalter, Stanford University; and J. J. Lissauer, Ames
Research Center, NASA, report the recovery of two inner Uranian
satellites, S/1986 U 10 (cf. IAUC 7171) and Uranus VII (Ophelia),
in recent data from the High Resolution Channel of the Hubble Space
Telescope (HST) Advanced Camera for Surveys. Images were obtained
during three consecutive HST orbits between Aug. 25.8042 and
25.9659 UT. This is the first clear groundbased detection of
either satellite and substantially reduces uncertainties in each
body's orbital mean motion. Each satellite is visible as a streak
in two consecutive coadded images, each consisting of four 250-s
clear-filter (300-900 nm) exposures. Uranus VII crossed the
southern ansa of Uranus's rings at Aug. 25.8819, trailing its
predicted orbital longitude by 62.8 +/- 1.3 deg. This slightly
exceeds the 58-deg uncertainty in its extrapolated orbit; the
implied change in its mean motion is -0.00977 deg/day, to 956.41856
+/- 0.00020 degrees/day. Uranus VII is approximately 15 percent as
bright as Uranus XIV (Belinda) in the images, with signal-to-noise
ratio (S/N) > 20. S/1986 U 10 crossed the northern ansa of the
rings at Aug. 25.8264, leading its predicted orbital longitude by
47.6 +/- 0.9 deg. This is consistent with the 64-deg uncertainty
in its extrapolated orbit; the implied change in its mean motion is
+0.00741 deg, to 564.24741 +/- 0.00014 deg/day. S/1986 U 10 is
approximately 8 percent as bright as Uranus XIV, with S/N > 10.
COMET C/2002 VQ_94 (LINEAR)
An apparently asteroidal object reported by LINEAR (announced
on MPEC 2002-V71, where B. G. Marsden noted "whether this object is
a comet or not is inconclusive", and MPS 66506; discovery
observation given below) has been found to have a prominent 10"
coma with a fanlike morphology spanning p.a. 180-300 deg on images
taken by D. Jewitt on Aug. 28.5 UT with the University of Hawaii
2.2-m telescope. Recent astrometry, the orbital elements below,
and an ephemeris appear on MPEC 2003-R22.
2002 UT R.A. (2000) Decl. Mag.
Nov. 11.23766 2 02 44.75 +46 00 35.6 18.7
Epoch = 2006 Jan. 25.0 TT
T = 2006 Feb. 6.6544 TT Peri. = 100.0365
e = 0.966862 Node = 35.0164 2000.0
q = 6.796699 AU Incl. = 70.5155
(C) Copyright 2003 CBAT
2003 September 3 (8194) Daniel W. E. Green
Read IAUC 8195
.dvi or
.ps format.
Our Web policy. Index to the CBAT/MPC/ICQ pages.
