Titan's forced rotation - Part II: The resonant wobble

Research output: Contribution in Book/Catalog/Report/Conference proceedingChapter

28 Downloads (Pure)

Abstract

Our knowledge of the gravity field of Titan has been recently improved thanks to the fly-bys of Cassini spacecraft, that provided us first values of Titan's J_2 and C_{22}, unfortunately without any indication of the polar inertial momentum C. Anyway, these data allowed us to give last year a first 3-dimensional description of the rotation of Titan, seen as a rigid body. In particular, we pointed out an interesting phenomenon forcing the wobble (i.e. the angular separation between Titan pole axis and angular momentum), that we suspected to be nearly resonant. This year we present a study of this resonance, involving a free libration around the Cassini equilibrium and a proper mode given by the orbital ephemerides. The resonant argument has been clearly identified, and its behaviour has been investigated using the Second Fundamental Model of Resonance. We show that in case of capture, the wobble might be pumped to several degrees. Moreover, we propose an original formula to estimate the contribution of the wobble in the tidal internal dissipation of a synchronous satellite. A significant wobble might cause a wrong estimation of the rotation of Titan.
Original languageEnglish
Title of host publicationScientific Highlights 2008
EditorsF Casoli, T Contini, J. M Hameury, L Pagani
PublisherEDP Sciences
Pages137-140
Number of pages4
Publication statusPublished - 2008

Fingerprint

Titan
ephemerides
momentum
synchronous satellites
libration
rigid structures
spacecraft
indication
poles
dissipation
angular momentum
gravitation
orbitals
causes
estimates

Cite this

Noyelles, B., Lemaître, A., & Vienne, A. (2008). Titan's forced rotation - Part II: The resonant wobble. In F. Casoli, T. Contini, J. M. Hameury, & L. Pagani (Eds.), Scientific Highlights 2008 (pp. 137-140). EDP Sciences.
Noyelles, Benoît ; Lemaître, Anne ; Vienne, Alain. / Titan's forced rotation - Part II: The resonant wobble. Scientific Highlights 2008. editor / F Casoli ; T Contini ; J. M Hameury ; L Pagani. EDP Sciences, 2008. pp. 137-140
@inbook{ee39600b655a4e2088701428e238ba6a,
title = "Titan's forced rotation - Part II: The resonant wobble",
abstract = "Our knowledge of the gravity field of Titan has been recently improved thanks to the fly-bys of Cassini spacecraft, that provided us first values of Titan's J_2 and C_{22}, unfortunately without any indication of the polar inertial momentum C. Anyway, these data allowed us to give last year a first 3-dimensional description of the rotation of Titan, seen as a rigid body. In particular, we pointed out an interesting phenomenon forcing the wobble (i.e. the angular separation between Titan pole axis and angular momentum), that we suspected to be nearly resonant. This year we present a study of this resonance, involving a free libration around the Cassini equilibrium and a proper mode given by the orbital ephemerides. The resonant argument has been clearly identified, and its behaviour has been investigated using the Second Fundamental Model of Resonance. We show that in case of capture, the wobble might be pumped to several degrees. Moreover, we propose an original formula to estimate the contribution of the wobble in the tidal internal dissipation of a synchronous satellite. A significant wobble might cause a wrong estimation of the rotation of Titan.",
author = "Beno{\^i}t Noyelles and Anne Lema{\^i}tre and Alain Vienne",
note = "Publication editors : F. Casoli, T. Contini, J.M. Hameury, L. Pagani",
year = "2008",
language = "English",
pages = "137--140",
editor = "F Casoli and T Contini and Hameury, {J. M} and L Pagani",
booktitle = "Scientific Highlights 2008",
publisher = "EDP Sciences",
address = "France",

}

Noyelles, B, Lemaître, A & Vienne, A 2008, Titan's forced rotation - Part II: The resonant wobble. in F Casoli, T Contini, JM Hameury & L Pagani (eds), Scientific Highlights 2008. EDP Sciences, pp. 137-140.

Titan's forced rotation - Part II: The resonant wobble. / Noyelles, Benoît; Lemaître, Anne; Vienne, Alain.

Scientific Highlights 2008. ed. / F Casoli; T Contini; J. M Hameury; L Pagani. EDP Sciences, 2008. p. 137-140.

Research output: Contribution in Book/Catalog/Report/Conference proceedingChapter

TY - CHAP

T1 - Titan's forced rotation - Part II: The resonant wobble

AU - Noyelles, Benoît

AU - Lemaître, Anne

AU - Vienne, Alain

N1 - Publication editors : F. Casoli, T. Contini, J.M. Hameury, L. Pagani

PY - 2008

Y1 - 2008

N2 - Our knowledge of the gravity field of Titan has been recently improved thanks to the fly-bys of Cassini spacecraft, that provided us first values of Titan's J_2 and C_{22}, unfortunately without any indication of the polar inertial momentum C. Anyway, these data allowed us to give last year a first 3-dimensional description of the rotation of Titan, seen as a rigid body. In particular, we pointed out an interesting phenomenon forcing the wobble (i.e. the angular separation between Titan pole axis and angular momentum), that we suspected to be nearly resonant. This year we present a study of this resonance, involving a free libration around the Cassini equilibrium and a proper mode given by the orbital ephemerides. The resonant argument has been clearly identified, and its behaviour has been investigated using the Second Fundamental Model of Resonance. We show that in case of capture, the wobble might be pumped to several degrees. Moreover, we propose an original formula to estimate the contribution of the wobble in the tidal internal dissipation of a synchronous satellite. A significant wobble might cause a wrong estimation of the rotation of Titan.

AB - Our knowledge of the gravity field of Titan has been recently improved thanks to the fly-bys of Cassini spacecraft, that provided us first values of Titan's J_2 and C_{22}, unfortunately without any indication of the polar inertial momentum C. Anyway, these data allowed us to give last year a first 3-dimensional description of the rotation of Titan, seen as a rigid body. In particular, we pointed out an interesting phenomenon forcing the wobble (i.e. the angular separation between Titan pole axis and angular momentum), that we suspected to be nearly resonant. This year we present a study of this resonance, involving a free libration around the Cassini equilibrium and a proper mode given by the orbital ephemerides. The resonant argument has been clearly identified, and its behaviour has been investigated using the Second Fundamental Model of Resonance. We show that in case of capture, the wobble might be pumped to several degrees. Moreover, we propose an original formula to estimate the contribution of the wobble in the tidal internal dissipation of a synchronous satellite. A significant wobble might cause a wrong estimation of the rotation of Titan.

M3 - Chapter

SP - 137

EP - 140

BT - Scientific Highlights 2008

A2 - Casoli, F

A2 - Contini, T

A2 - Hameury, J. M

A2 - Pagani, L

PB - EDP Sciences

ER -

Noyelles B, Lemaître A, Vienne A. Titan's forced rotation - Part II: The resonant wobble. In Casoli F, Contini T, Hameury JM, Pagani L, editors, Scientific Highlights 2008. EDP Sciences. 2008. p. 137-140