TY - JOUR

T1 - Behavior of nearby synchronous rotations of a Poincaré-Hough satellite at low eccentricity

AU - Noyelles, Benoît

N1 - Copyright 2012 Elsevier B.V., All rights reserved.

PY - 2012/4/1

Y1 - 2012/4/1

N2 - This paper presents a study of the Poincaré-Hough model of rotation of the synchronous natural satellites, in which these bodies are assumed to be composed of a rigid mantle and a triaxial cavity filled with inviscid fluid of constant uniform density and vorticity. In considering an Io-like body on a low eccentricity orbit, we describe the different possible behaviors of the system, depending on the size, polar flattening and shape of the core. We use for that the numerical tool. We propagate numerically the Hamilton equations of the system, before expressing the resulting variables under a quasi-periodic representation. This expression is obtained numerically by frequency analysis. This allows us to characterise the equilibria of the system, and to distinguish the causes of their time variations. We show that, even without orbital eccentricity, the system can have complex behaviors, in particular when the core is highly flattened. In such a case, the polar motion is forced by several degrees and longitudinal librations appear. This is due to splitting of the equilibrium position of the polar motion. We also get a shift of the obliquity when the polar flattening of the core is small.

AB - This paper presents a study of the Poincaré-Hough model of rotation of the synchronous natural satellites, in which these bodies are assumed to be composed of a rigid mantle and a triaxial cavity filled with inviscid fluid of constant uniform density and vorticity. In considering an Io-like body on a low eccentricity orbit, we describe the different possible behaviors of the system, depending on the size, polar flattening and shape of the core. We use for that the numerical tool. We propagate numerically the Hamilton equations of the system, before expressing the resulting variables under a quasi-periodic representation. This expression is obtained numerically by frequency analysis. This allows us to characterise the equilibria of the system, and to distinguish the causes of their time variations. We show that, even without orbital eccentricity, the system can have complex behaviors, in particular when the core is highly flattened. In such a case, the polar motion is forced by several degrees and longitudinal librations appear. This is due to splitting of the equilibrium position of the polar motion. We also get a shift of the obliquity when the polar flattening of the core is small.

UR - http://www.scopus.com/inward/record.url?scp=84859500558&partnerID=8YFLogxK

U2 - 10.1007/s10569-012-9398-y

DO - 10.1007/s10569-012-9398-y

M3 - Article

AN - SCOPUS:84859500558

SN - 0923-2958

VL - 112

SP - 353

EP - 383

JO - Celestial Mechanics & Dynamical Astronomy

JF - Celestial Mechanics & Dynamical Astronomy

IS - 4

ER -