Theory of Rotation for the Planet Mercury

  title={Theory of Rotation for the Planet Mercury},
  author={Han-shou Liu and John A. O'keefe},
  pages={1717 - 1717}
The theory of the rotation of the planet Mercury is developed in terms of the motion of a rigid system in an inverse-square field. It is possible for Mercury to rotate with a period exactly two-thirds of the period of revolution; there is a libration with a period of 25 years. 
Rotation of the Planet Mercury
The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion and it is confirmed that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution.
Rotation of Mercury: Theoretical Analysis of the Dynamics of a Rigid Ellipsoidal Planet
The second-order nonlinear differential equation for the rotation of Mercury implies locked-in motion when the period is within the range where e is the eccentricity and T is the period of Mercury's
The libration of Mercury
In a recent report [Liu and O'Keefe, 1965], we presented the analysis of the resonance-locked rotation of the planet Mercury under the influence of the planetary potential and the orbital
On the figure of the planet Mercury
The figure of Mercury is estimated in terms of an isostatic form of equilibrium which tends to be controlled by the situation near perihelion passage at the 3∶2 resonance spin rate. The ratios of the
The planet Mercury (1971)
  • Nasa
  • Physics, Geology
  • 2019
The physical properties of the planet Mercury, its surface, and atmosphere are presented for space vehicle design criteria. The mass, dimensions, mean density, and orbital and rotational motions are
Rotation and Heating of the Planet Mercury
RECENT radar observations1 and subsequent discussions2,3 indicate that the rotational period of Mercury may be coupled4 to its orbital period in the ratio 2 : 3. Here we examine the insolation and
Passage Through Resonance
The effect of both gravitational and tidal torques on the spin rate of the planet Mercury is used as a model for a passage through resonance problem. Both the resonance and nonresonance aspects of
Thermal and tidal effect on the rotation of Mercury
It is shown that the influences of the thermal and tidal effects on Mercury's libration are in equilibrium with the periods of rotation and revolution of Mercury locked in the 3∶2 resonant state. The
A note on the instantaneous rotational velocity of Mercury
The fluctuation in the angular velocity of the present rotation of Mercury is investigated. The instantaneous rotational rate in terms of orbital mean motion at different positions along Mercury's
Mercury: Magnetic field and interior
Between 1965 and 1975, our knowledge of Mercury and its physical characteristics improved dramatically. Radar studies of the planetary orbit and rotation rate and Mariner 10 spacecraft studies of its


Rotation of the Planet Mercury
SOLAR tidal friction must be an intense effect for Mercury, and it must be expected that the planet's spin would have relaxed from any original value to one that is under the control of this effect
Rotation Period of the Planet Mercury
THE recent radar measurements of Mercury indicate that the period of rotation of the planet is 59 ± 5 days1. This result is in complete disagreement with the previously quoted value of 88 days based
Rotational Period of the Planet Mercury
IN a recent communication by S. J. Peale and T. Gold1 the rotational period of Mercury, determined from radar Doppler-spread measurements to be 59 ± 5 days2, has been explained in terms of a solar
Tidal De-spin of Planets and Satellites
RECENTLY, Peale and Gold1 have shown that the non-synchronous rotation of Mercury is likely to be a consequence of tidal friction. They point out that in an eccentric orbit the spin of an axially
Lancaster for assistance. The numerical analysis was performed by