Past Orientation of the Lunar Spin Axis

@article{Ward1975PastOO,
  title={Past Orientation of the Lunar Spin Axis},
  author={W. Ward},
  journal={Science},
  year={1975},
  volume={189},
  pages={377 - 379}
}
  • W. Ward
  • Published 1975
  • Physics, Medicine
  • Science
The orientation of the lunar spin axis is traced from the early history of the earth-moon system to the present day. Tides raised on the earth by the moon have caused an expansion of the lunar orbit. Tides raised on the moon by the earth have de-spun the moon to synchronous rotation and driven its spin axis to a Cassini state—that is, in a coprecessing configuration, coplanar with the lunar orbit normal and the normal to the Laplacian plane (which is at present coincident with the normal to the… Expand

Topics from this paper

Tidal Evolution of the Earth–Moon System with a High Initial Obliquity
A giant-impact origin for the Moon is generally accepted, but many aspects of lunar formation remain poorly understood and debated. Ćuk et al. proposed that an impact that left the Earth–Moon systemExpand
Tidal evolution of the Moon from a high-obliquity, high-angular-momentum Earth
TLDR
It is shown that tidal dissipation due to lunar obliquity was an important effect during the Moon’s tidal evolution, and the lunar inclination in the past must have been very large, defying theoretical explanations. Expand
Early Dynamics of the Lunar Core
The Moon is known to have a small liquid core, and it is thought that in the distant past the core may have produced strong magnetic fields recorded in lunar samples. Here we implement a numericalExpand
The rigid body obliquity history of Mars
The primary objective of this study is to explore the range of uncertainty in the obliquity history of Mars associated with the present uncertainty in the axial precession rate. The obliquity, orExpand
DYNAMICS OF THE LUNAR SPIN AXIS
The evolution of the lunar spin axis is studied. Prior work has assumed that the inclination of the lunar orbit is constant and that the node regresses uniformly. This work takes into account theExpand
Precession of the Lunar Core
Abstract Goldreich (Goldreich, P. [1967]. J. Geophys. Res. 72, 3135) showed that a lunar core of low viscosity would not precess with the mantle. We show that this is also the case for much of lunarExpand
Tides on the Moon: Theory and determination of dissipation
Solid body tides on the Moon vary by about ±0.1 m each month. In addition to changes in shape, the Moon's gravity field and orientation in space are affected by tides. The tidal expressions for anExpand
Lunar true polar wander inferred from polar hydrogen
TLDR
The hypothesis that true polar wander was caused by a low-density thermal anomaly beneath the Procellarum region implies that polar wander initiated billions of years ago and that a large portion of the measured polar hydrogen is ancient, recording early delivery of water to the inner Solar System. Expand
Tidal dissipation in the lunar magma ocean and its effect on the early evolution of the Earth–Moon system
Abstract The present-day inclination of the Moon reflects the entire history of its thermal and orbital evolution. The Moon likely possessed a global magma ocean following the Moon-forming impact. InExpand
Lunar Polar Ice and the Obliquity History of the Moon
Water ice is currently stable from sublimation loss in shadowed environments near the lunar poles. However, most current temperature environments are generally too cold to allow efficient diffusiveExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 10 REFERENCES
The history of the lunar orbit
A method of calculating the past states of the earth-moon system is developed. The method is based on the existence of three distinct time scales for dynamical change. The short time scale isExpand
I. The formation of planetesimals. II. Tidal friction and generalized Cassini's laws in the solar system
The tidal drift toward a generalized Cassini state of rotation of the spin axis of a planet or satellite in a precessing orbit is described. Generalized Cassini's laws are applied to several solarExpand
Possible histories of the obliquity of Mercury
Possible evolutionary paths of the spin axis of Mercury are studied theoretically in terms of generalized Cassini's laws using the Hamiltonian approach. Three stable positions (Cassini states) of theExpand
Origin of the moon by tidal capture and some geophysical consequences
Of the many proposed modes of origin of the Moon, some violate physical laws; many are in conflict with observations; all are improbable. Perhaps the least improbable - based on recent tidal theoryExpand
Some remarks on polar wandering
This paper lends fresh support to the hypothesis that large angular displacements of the earth's rotation axis relative to the entire mantle have occurred on a geological time scale, owing to theExpand
Generalized Cassini's laws
Cassini laws applied to moon and Mercury, determining relations between moment differences for spin vector, orbital angular-momentum vector and precessional velocity
The obliquity of Venus
Venus obliquity dynamic implications, developing equations for independent parameter set to define spin vector
Comments on lunar origin.
Cassini's second and third laws
Traite de L'Origini ede Progres de L'Astronomie