The effect of Jupiter's mass growth on satellite capture

Free access article

Issue		A&A Volume 414, Number 2, February I 2004


Page(s)		727 - 734
Section		The Sun
DOI		http://dx.doi.org/10.1051/0004-6361:20031645

A&A 414, 727-734 (2004)
DOI: 10.1051/0004-6361:20031645

Retrograde case

E. Vieira Neto¹, O. C. Winter¹ and T. Yokoyama²

¹ Grupo de Dinâmica Orbital & Planetologia, UNESP, CP 205 CEP 12.516-410 Guaratinguetá, SP, Brazil
e-mail: ernesto@feg.unesp.br
² Universidade Estadual Paulista, IGCE, DEMAC, CP 178 CEP 13.500-970 Rio Claro, SP, Brazil
e-mail: tadashi@ms.rc.unesp.br

(Received 13 June 2003 / Accepted 12 September 2003 )

Abstract
Gravitational capture can be used to explain the existence of the irregular satellites of giants planets. However, it is only the first step since the gravitational capture is temporary. Therefore, some kind of non-conservative effect is necessary to to turn the temporary capture into a permanent one. In the present work we study the effects of Jupiter mass growth for the permanent capture of retrograde satellites. An analysis of the zero velocity curves at the Lagrangian point L₁ indicates that mass accretion provides an increase of the confinement region (delimited by the zero velocity curve, where particles cannot escape from the planet) favoring permanent captures. Adopting the restricted three-body problem, Sun-Jupiter-Particle, we performed numerical simulations backward in time considering the decrease of $M_{\jupiter}$ . We considered initial conditions of the particles to be retrograde, at pericenter, in the region $100~ R_{\jupiter} \leq a\leq 400 ~R_{\jupiter}$ and $0 \leq e \leq 0.5$ . The results give Jupiter's mass at the moment when the particle escapes from the planet. Such values are an indication of the necessary conditions that could provide capture. An analysis of these results shows that retrograde satellites would be captured as soon as they get inside the Hills' radius and after that they keep migrating toward the planet while it is growing. For the region where the orbits of the four "old" retrograde satellites of Jupiter (Ananke, Carme, Pasiphae and Sinope) are located we found that such satellites could have been permanently captured when Jupiter had between $62\%$ and $93\%$ of its present mass.

Key words: planets and satellites: general -- astrometry -- celestial mechanics

Offprint request: O. C. Winter, ocwinter@feg.unesp.br

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.

If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.