Quasi-Hilda Comet 147P/Kushida-Muramatsu: Another long temporary satellite capture by Jupiter
K. Ohtsuka, T. Ito, M. Yoshikawa, D.J. Asher and H. Arakida
Astron. Astrophys., 489, 1355-1362 (2008)
Abstract:
Context.
The quasi-Hilda comets (QHCs), being in unstable 3:2 Jovian mean motion
resonance, are considered a major cause of temporary satellite capture (TSC)
by Jupiter. Although the QHCs may be escaped Hilda asteroids, their origin
and nature have not yet been studied in sufficient detail. Of particular
interest are long TSCs/orbiters. Orbiters - in which at least one full
revolution about the planet is completed - are rare astronomical events,
because only four have been known to occur in the last several decades.
Every case has been associated with a QHC: 82P/Gehrels 3,
111P/Helin-Roman-Crockett, P/1996 R2 (Lagerkvist), and the possibly
QHC-derived D/1993 F2 (Shoemaker-Levy 9, SL9).
Aims.
We focus on long TSC/orbiter events involving QHCs and Jupiter. Thus we
survey the known QHCs, searching for other long TSCs/orbiters over the past
century.
Methods.
First, we confirmed the long TSC/orbiter events of 82P, 111P, and 1996 R2 in
order to test our method against previous work, applying a general N-body
Newtonian code. We then used the same procedure to survey the remaining
known QHCs and search for long TSC/orbiter events.
Results.
We newly identified another long TSC/orbiter: 147P/Kushida-Muramatsu from
1949 May 14 [+97 days] [-106 days] - 1961 July 15. Our result is verified by
integrations of 243 cloned orbits that take account of the present orbital
uncertainty of this comet. The event involves an L2 to L1 transition as with
82P and 1996 R2. This may represent a distinct subtype of TSCs from
QHC-derived (L1 $\to$) longer captures exemplified by 111P and (probably)
SL9, though this classification is still only based on a small database of
TSCs.
Conclusions.
This is the third long TSC and the fifth orbiter to be found, thus long
TSC/orbiter events involving Jupiter have occurred once per decade. Two full
revolutions about Jupiter were completed and the capture duration was 12.17
[+0.29] [-0.27] years. Both these numbers rank 147P as third among long
TSC/orbiter events, behind SL9 and 111P. This study also confirms the
importance of the QHC region as a dynamical route into and out of Jovian TSC,
via the Hill's sphere.
Full Paper - PDF
Published version at A&A