Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-12-05T02:46:21.524Z Has data issue: false hasContentIssue false
  • English
  • Français

An Accurate Model of Mercury’s Spin-Orbit Motion

Published online by Cambridge University Press:  30 March 2016

Nicolas Rambaux  and
Eric Bois
Nicolas Rambaux
Affiliation:
Observatoire Aquitain des Sciences de l’Univers, UMR L3AB CNRS/INSU 5804, B.P. 89, F-33270 FloiracFrance
Eric Bois
Affiliation:
Observatoire Aquitain des Sciences de l’Univers, UMR L3AB CNRS/INSU 5804, B.P. 89, F-33270 FloiracFrance

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Our work deals with the physical and dynamical causes that induce librations of Mercury around an equilibrium state defined by the 3:2 spin-orbit resonance. In order to integrate the spin-orbit motion of Mercury, we have used our gravitational model of the solar system including the Moon’s spin-orbit motion. This model, called SONYR (acronym of Spin-Orbit N-bodY Relativistic model), was previously built by Bois, Journet and Vokrouhlicky in accordance with the requirements of the Lunar Laser Ranging observational accuracy.

Using the model, we have identified the main perturbations acting on the spin-orbit motion of Mercury such as the planetary interactions or the dynamical figure of the planet. Moreover, the complete rotation of Mercury exhibits two proper frequencies, namely 15.847 and 1066 years, and in addition one spin-orbit secular resonance (298 898 years). A new determination of the mean obliquity of Mercury has been proposed. Besides, we have identified in the Hermean librations the impact of the uncertainty of the greatest principal moment of inertia (C/MR2) on the obliquity as well as on the libration in longitude (2.3 mas and 0.45 as respectively for an increase of 1% on the C/MR2 value). These accurate relations have to be taken into account in the context of the two upcoming missions BepiColombo and MESSENGER.

Type
I. Joint Discussions
Information
Highlights of Astronomy , Volume 13 , 2005 , pp. 64 - 66
Copyright
Copyright © Astronomical Society of Pacific 2005

References

Balogh, A., & Giamperi, G., 2002, Rep.Prog.Phys., 65, 529 Google Scholar
Bois, E., & Vokrouhlicky, D., 1995, A & A, 300, 559 Google Scholar
Bois, E., 1995, A & A 296, 850 Google Scholar
Bois, E., 2000, C. R. Acad. Sci. Paris, T. 1, Serie IV, p. 809–823 Google Scholar
Milani, A., Vokrouhlicky, D., & Bonanno, C., 2001, Planetary and Space Science, 49, 1579 Google Scholar
Rambaux, N., & Bois, E., A & A, 401, 381 Google Scholar
Solomon, S.C., et al., 2001, Planetary and Space Science, 49, 1445 Google Scholar