The Reverse Side of the Moon

1962 ◽  
Vol 14 ◽  
pp. 3-6
Author(s):  
A. A. Mikhailov
Keyword(s):  
Axial Rotation ◽  
The Moon ◽  
Tidal Friction ◽  
Human Eye ◽  
The Earth ◽  
Entire Time

During the entire time of Earth's existence the human eye has never seen the reverse side of the Moon. It is quite probable that, initially, the Moon had an axial rotation relative to the Earth, but tidal friction slowed this rotation down to such an extent that the Moon remained forever with one side turned towards the Earth.

scholarly journals Dissipation Of Tidal Energy By Flexing Ice Shelves

1979 ◽  
Vol 24 (90) ◽  
pp. 482-482
Author(s):  
C. S. M. Doake
Keyword(s):  
Plastic Deformation ◽  
Tidal Energy ◽  
Single Source ◽  
The Moon ◽  
Tidal Friction ◽  
Ice Shelves ◽  
Source Contribution ◽  
The Earth ◽  
Grounding Line ◽  
Rotation Of The Earth

Plastic deformation of ice shelves in the region along the grounding line where they bend with the tide can dissipate enough tidal energy to make them the most important single source contribution to tidal friction (Doake, 1978). Some of the effects are to slow the rotation of the Earth and to cause the moon to retreat from the Earth.

scholarly journals Historic Variations in the Rotation of the Earth

1972 ◽  
Vol 48 ◽  
pp. 160-161
Author(s):  
R. R. Newton
Keyword(s):  
Earth’S Rotation ◽  
The Moon ◽  
Earth's Rotation ◽  
Tidal Friction ◽  
The Past ◽  
The Earth ◽  
Rotation Of The Earth

The purpose of this work is to investigate changes in the rotation of the Earth in the past few thousand years. Since most available observations involve the Moon, study of the Earth's rotation is inseparable from study of the Moon's motion. Since it is doubtful that present theories of tidal friction account for the present acceleration (Spencer Jones, 1939; Van Flandern, 1970; Pariisky et al., 1972) of the Moon, we cannot safely assume that consequence of the theories which says that tidal friction has been almost constant.

Tidal friction in the Earth-Moon system

1984 ◽  
Vol 313 (1524) ◽  
pp. 71-75 ◽  
Keyword(s):  
The Moon ◽  
Tidal Friction ◽  
Moon System ◽  
Tidal Torque ◽  
Original State ◽  
The Earth

Modern computers enable us to obtain realistic values for the present tidal torque between the Moon and the oceans; those values agree with the observations. In principle, computations for distant geological epochs are possible as well and have been performed. However, the very complex eigenperiod spectrum of the oceans today precludes a continuous reconstruction of the tidal torque for an essential part of the Earth’s history. Hence the original state of the Earth-Moon system is still uncertain. We emphasize the importance of results for intermediate timescales.

scholarly journals Dissipation Of Tidal Energy By Flexing Ice Shelves

1979 ◽  
Vol 24 (90) ◽  
pp. 482
Author(s):  
C. S. M. Doake
Keyword(s):  
Plastic Deformation ◽  
Tidal Energy ◽  
Single Source ◽  
The Moon ◽  
Tidal Friction ◽  
Ice Shelves ◽  
Source Contribution ◽  
The Earth ◽  
Grounding Line ◽  
Rotation Of The Earth

Plastic deformation of ice shelves in the region along the grounding line where they bend with the tide can dissipate enough tidal energy to make them the most important single source contribution to tidal friction (Doake, 1978). Some of the effects are to slow the rotation of the Earth and to cause the moon to retreat from the Earth.

Modelling moving force of tectonic plates with the use of length of day variation

2021 ◽  
Author(s):  
Csilla Fodor ◽  
Péter Varga
Keyword(s):  
Plate Tectonics ◽  
Axial Rotation ◽  
Rotational Energy ◽  
Plate Motion ◽  
Orbital Energy ◽  
Depth Interval ◽  
Length Of Day ◽  
Tidal Friction ◽  
Tectonic Plates ◽  
The Earth

<p>The nature, the age and probably first of all the magnitude of driving forces of plate motion since long are a subject of scientific debates and it cannot be regarded as clarified even today.</p><p>The physical basis of recent plate tectonics is characterized by interaction between plates by viscous coupling to a convecting mantle.  Authors are going to demonstrate that changes in the Earth's axial rotation can affect the movement of tectonic plates, and the phenomenon of tidal friction is able to shift the lithospheric plates.</p><p>The tidal friction regulates the length of day (LOD)and consequently also the rotational energy of the Earth. It can be investigated with the use of total tidal energy<sub>, </sub>which can be determined as a sum of three energies (energy of axial rotation of the Earth, Moon’s orbital energy around the common centre of mass and the mutual potential energy). It was found that during the last 3 Ga the Earth lost 33% of its rotational energy. The LOD 0.5Ga BP (before present) was ~21 h. This means that the rotational energy loss rate was 4.1 times higher during the Pz (Phanerozoic, from 560 Ma BP to our age) than earlier in the Arch (Archean, 4 to 2.5 Ga BP) and Ptz (Proterozoic 2.5 to0.56 Ga BP). The low-velocity zone (LVZ) at 100-200 km depth interval, close to the boundary between the lithosphere and the asthenosphere characterized by a negative anomaly of shear wave velocities. Consequently, the LVZ can result in a decoupling effect. Tidal friction brakes the lithosphere and the part of the Earth below the asthenosphere with different forces. By model calculation, we show that this force difference is sufficient to move the tectonic plates along the Earth’s surface.  </p><p>Reference: Varga P., Fodor Cs., 2021. About the energy and age of the plate tectonics, Terra Nova. (in print) https://doi.org/10.1111/ter.12518</p>

The importance of tidal friction for the early history of the Moon

1967 ◽  
Vol 296 (1446) ◽  
pp. 293-297 ◽  
Keyword(s):  
Body Problem ◽  
Early History ◽  
The Moon ◽  
Tidal Friction ◽  
Moon System ◽  
Two Body Problem ◽  
Dissipation Of Energy ◽  
The Earth ◽  
History Of ◽  
Rotation Of The Earth

About ten years ago I began to investigate tidal friction and its influence on the evolution of the Earth-Moon system, and I first describe the model used. Following the ideas of G. H. Darwin, I treated the system as a two-body problem. The Moon raises tides on the Earth and the two bulges of the tidal ellipsoid, because of the rotation of the Earth, revolve twice daily. The line joining them forms an angle ψ with the line joining their centres; this is a measure of the dissipation of energy. The Moon, considered as a point mass, exerts a retarding couple on the deviated tidal ellipsoid. Contrary to Darwin, I have limited myself to the case of small angles ψ , but I have allowed for arbitrary changes of the other parameters of the orbit, for example, changes of the obliquity ∊ between the earth’s axis and the pole of the orbit as well as changes of the eccentricity.

Le Lien Gravitationnel Terre-Lune à Travers les Ages

1972 ◽  
Vol 9 (5) ◽  
pp. 479-485
Author(s):  
Jean-Maurice Chevallier ◽  
André Cailleux
Keyword(s):  
Angular Momentum ◽  
Biological Rhythms ◽  
The Moon ◽  
Daily Growth ◽  
Tidal Friction ◽  
Growth Increments ◽  
The Earth ◽  
Order Of Magnitude ◽  
Good Concordance ◽  
Remote Past

The authors expressed the view in 1952 that tidal friction between the earth and moon could account for many features such as alterations in biological rhythms, or tectonic effects of unequalled amplitude throughout geological times and the remote past. Tests for this theory are: (a) It is remarkable that the loss of angular momentum by the earth since the "original" state almost exactly matches the amount required to bring the moon from the earth's equator to its present orbit; (b) Recent observations of daily growth increments in fossil organisms show, at least for the last 400 m.y., that the order of magnitude of the time-scale previously adopted by the authors is satisfactory, the scale having only to be somewhat shortened and the values—theoretical and observed—of the month-to-day ratio are in good concordance.

The motion of a lunar orbiter

1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai
Keyword(s):  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Artificial Satellite ◽  
Equations Of Motion ◽  
Triaxial Ellipsoid ◽  
The Moon ◽  
Secular Motion ◽  
The Earth ◽  
Close Satellite ◽  
The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Origin of the Moon

1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
The Moon ◽  
The Earth ◽  
The Difference ◽  
Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

Sign in / Sign up

Export Citation Format

Share Document