Space Science Reviews

, Volume 131, Issue 1, pp 105–132

The Geophysics of Mercury: Current Status and Anticipated Insights from the MESSENGER Mission

  • Maria T. Zuber
  • Oded Aharonson
  • Jonathan M. Aurnou
  • Andrew F. Cheng
  • Steven A. HauckII
  • Moritz H. Heimpel
  • Gregory A. Neumann
  • Stanton J. Peale
  • Roger J. Phillips
  • David E. Smith
  • Sean C. Solomon
  • Sabine Stanley
Article

DOI: 10.1007/s11214-007-9265-4

Cite this article as:
Zuber, M.T., Aharonson, O., Aurnou, J.M. et al. Space Sci Rev (2007) 131: 105. doi:10.1007/s11214-007-9265-4

Abstract

Current geophysical knowledge of the planet Mercury is based upon observations from ground-based astronomy and flybys of the Mariner 10 spacecraft, along with theoretical and computational studies. Mercury has the highest uncompressed density of the terrestrial planets and by implication has a metallic core with a radius approximately 75% of the planetary radius. Mercury’s spin rate is stably locked at 1.5 times the orbital mean motion. Capture into this state is the natural result of tidal evolution if this is the only dissipative process affecting the spin, but the capture probability is enhanced if Mercury’s core were molten at the time of capture. The discovery of Mercury’s magnetic field by Mariner 10 suggests the possibility that the core is partially molten to the present, a result that is surprising given the planet’s size and a surface crater density indicative of early cessation of significant volcanic activity. A present-day liquid outer core within Mercury would require either a core sulfur content of at least several weight percent or an unusual history of heat loss from the planet’s core and silicate fraction. A crustal remanent contribution to Mercury’s observed magnetic field cannot be ruled out on the basis of current knowledge. Measurements from the MESSENGER orbiter, in combination with continued ground-based observations, hold the promise of setting on a firmer basis our understanding of the structure and evolution of Mercury’s interior and the relationship of that evolution to the planet’s geological history.

Keywords

MercuryMESSENGERCoreRotational stateMagnetic dynamosThermal history

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Maria T. Zuber
    • 1
  • Oded Aharonson
    • 2
  • Jonathan M. Aurnou
    • 3
  • Andrew F. Cheng
    • 4
  • Steven A. HauckII
    • 5
  • Moritz H. Heimpel
    • 6
  • Gregory A. Neumann
    • 1
    • 7
  • Stanton J. Peale
    • 8
  • Roger J. Phillips
    • 9
  • David E. Smith
    • 7
  • Sean C. Solomon
    • 10
  • Sabine Stanley
    • 1
    • 11
  1. 1.Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaUSA
  3. 3.Department of Earth and Space SciencesUniversity of CaliforniaLos AngelesUSA
  4. 4.The Johns Hopkins University Applied Physics LaboratoryLaurelUSA
  5. 5.Department of Geological SciencesCase Western Reserve UniversityClevelandUSA
  6. 6.Department of PhysicsUniversity of AlbertaEdmontonCanada
  7. 7.Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltUSA
  8. 8.Department of PhysicsUniversity of CaliforniaSanta BarbaraUSA
  9. 9.Department of Earth and Planetary SciencesWashington UniversitySt. LouisUSA
  10. 10.Department of Terrestrial MagnetismCarnegie Institution of WashingtonWashingtonUSA
  11. 11.Department of PhysicsUniversity of TorontoTorontoCanada