Tidal origin of the Laplace resonance and the resurfacing of Ganymede

Research output: Contribution to journalArticlepeer-review

84 Scopus citations

Abstract

I present a new scenario for the tidal origin of the Laplace resonance. The inner three Galilean satellites are supposed to have formed in orbits well away from the 2/1 pair-wise mean motion commensurabilities and the three body Laplace resonance. The dynamics is controlled by the evolution of the 2/1 critical frequencies, ω1 = 2n2 - n1 and ω2 = 2n3 - n2, where n1, n2, n3 are the mean motions of Io, Europa, and Ganymede. I show that the Laplace relation, ω1 = ω2, may have been established from within a previous three body resonance defined by ω1 ω2 ≈ 1 2. The ω1 ω2 ≈ 1 2 resonance would have excited Ganymede's orbital eccentricity to a high value. The attendant enhanced tidal heating in Ganymede during that high eccentricity period provides a possible explanation for the geologically younger surface of Ganymede compared to that of its "twin satellite," Callisto. The extent of orbital evolution required for this scenario is easily accomodated by values of QJ of several times 105.

Original languageEnglish (US)
Pages (from-to)399-412
Number of pages14
JournalIcarus
Volume94
Issue number2
DOIs
StatePublished - Dec 1991
Externally publishedYes

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'Tidal origin of the Laplace resonance and the resurfacing of Ganymede'. Together they form a unique fingerprint.

Cite this