Earth's Rotation Is Slowing Down And The Culprit Is The Moon

2018 ◽  
Author(s):  
Kate Broome
Keyword(s):  
Earth’S Rotation ◽  
The Moon ◽  
Earth's Rotation ◽  
Slowing Down

scholarly journals Commission 19: Rotation of the Earth

1985 ◽  
Vol 19 (1) ◽  
pp. 193-205 ◽  
Author(s):  
Ya. S. Yatskiv ◽  
W. J. Klepczynski ◽  
F. Barlier ◽  
H. Enslin ◽  
C. Kakuta ◽  
...  
Keyword(s):  
Time Frame ◽  
Laser Ranging ◽  
Earth’S Rotation ◽  
The Moon ◽  
Earth's Rotation ◽  
The Earth ◽  
Long Time ◽  
Terrestrial Reference System ◽  
Rotation Of The Earth

During the period, work on the problem of the Earth’s rotation has continued to expand and increase its scope. The total number of institutions engaged in the determination of the Earth’s rotation parameters (ERP) by different techniques has been increased significantly. The rotation of the Earth is currently measured by classical astrometry, Doppler and laser satellite tracking, laser ranging of the Moon, and radio interferometry. Several long time series of the ERP are available from most of these techniques, in particular, those made during the Main Campaign of the MERIT project. The various series have been intercompared and their stability, in the time frame of years to days, has been estimated for the purposes of establishing a new conventional terrestrial reference system (COTES). On the other hand, the difficulties of maintaining a regular operation for laser ranging to the Moon (LLR) have been recognized. It resulted in the proposal to organize an one-month campaign of observations in 1985 in order to complement the COTES collocation program and to allow additional intercomparisons with other techniques.

scholarly journals On the Eclipse of Hipparchus

2019 ◽  
Vol 50 (1) ◽  
pp. 3-15
Author(s):  
Leslie V. Morrison ◽  
F. Richard Stephenson ◽  
Catherine Y. Hohenkerk
Keyword(s):  
Earth’S Rotation ◽  
The Moon ◽  
Earth's Rotation

We investigate the date of observation of the Hipparchus eclipse using our latest measurement of historical variations in the Earth’s rotation to plot the tracks of the potential eclipses. We conclude that Hipparchus most probably analysed the eclipse of −189 in deriving the distance to the Moon, as concluded by Toomer in 1974.

scholarly journals The oceans and the Earth's rotation

1988 ◽  
Vol 128 ◽  
pp. 349-352
Author(s):  
P. Brosche
Keyword(s):  
Solid Earth ◽  
Earth’S Rotation ◽  
The Moon ◽  
Tidal Effects ◽  
Earth's Rotation ◽  
Tidal Friction ◽  
Long Run ◽  
Short Time ◽  
Tidal Variations ◽  
Observational Techniques

In the long run, the tidal interaction between the Moon and the solid Earth is mediated by the oceans. It produces the retardation of the Earth's rotation known as ‘tidal friction’. Due to the changing configuration of the continents, it is a non-monotonic function of time. Tides of the solid Earth dominate the short-periodic tidal effects while the exchange with the atmosphere is preponderant in climatic changes, especially with an annual signature. It is shown that the influences of the oceans within such short time-scales must be taken into account for tidal and for non-tidal variations as well if one wants to model the Earth's rotation at the cm-level corresponding to the most advanced observational techniques.

Concluding remarks

1974 ◽  
Vol 276 (1257) ◽  
pp. 273-275
Keyword(s):  
Forest Cover ◽  
Expert Knowledge ◽  
Earth’S Rotation ◽  
Earth's Rotation ◽  
Slowing Down ◽  
Individual Contributions ◽  
Ancient Manuscripts ◽  
Historical Times ◽  
Plant Pollen

It would be very difficult to produce a coherent summary of such a wide-ranging meeting, with so many excellent individual contributions, and I shall not try. Instead I should like to discuss certain features of the meeting that particularly appealed to me; and on this occasion I speak as a semi-mathematician and semi-astronomer, without any specialized knowledge of antiquity. This meeting was intended to help in building bridges between science and history, or to be more accurate, between scientists and historians; and to convince both groups that bridges improve the quality of life - that each subject is enriched by an injection of the other. There were many examples, of which I will mention just three. First, Dr Needham, whose great work on Science and civilization in China is an example to us all, in the very best sense. Then there is Dr Newton’s work on the Earth’s rotation rate. This depends essentially on ancient manuscripts and similar material. But his results are of great scientific importance in the study of the EarthMoon system, because the slowing down of the Earth’s rotation depends on the orbital behaviour of the Moon, the shape of the oceans (which affects the tides), the goings-on in the Earth’s interior, and probably other unknown factors. A decision between the conflicting theories of the Moon’s origin, and an understanding of the Earth’s internal workings, may well be brought nearer by studies similar to Dr Newton’s: he has shown scientists how they must not neglect history. My third example is Professor Lamb’s paper on climate and forest cover in the ancient world. Although he needed his expert knowledge in meteorology, over 80 % of the references in his paper are primarily concerned not with meteorology at all, but with fossil coleoptera, Welsh and Irish bogs, sightings of comets, the Nile floods, deep-sea oozes, analysing plant pollen, changes in sea level, the spread of spruce trees, and so on. And his results are also wide-ranging in implication, being important not only for solar physicists trying to decide how and why the Sun’s radiation varies, but also for historians, because changes in climate have certainly contributed to the fall of empires in historical times, as well as governing the migrations of prehistoric peoples

scholarly journals New Approach to the Earth’s Rotation Problem Consistent with the General Planetary Theory

1997 ◽  
Vol 165 ◽  
pp. 301-306 ◽  
Author(s):  
V.A. Brumberg ◽  
T. V. Ivanova
Keyword(s):  
Earth’S Rotation ◽  
Planetary Theory ◽  
The Moon ◽  
Euler Parameters ◽  
Earth's Rotation ◽  
New Approach ◽  
Poisson Equations ◽  
Translatory Motion ◽  
Lunar Evolution ◽  
General Planetary Theory

AbstractThe equations of the translatory motion of the major planets and the Moon and the Poisson equations of the Earth’s rotation in Euler parameters are reduced to the secular system describing the evolution of the planetary and lunar orbits (independent of the Earth’s rotation) and the evolution of the Earth’s rotation (depending on the planetary and lunar evolution).

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.

scholarly journals Notes concerning tidal oscillations upon a rotating globe

1909 ◽  
Vol 82 (556) ◽  
pp. 448-464 ◽  
Keyword(s):  
Southern Ocean ◽  
Free Oscillation ◽  
Earth’S Rotation ◽  
The Sun ◽  
The Moon ◽  
Earth's Rotation

Speculations on tidal questions are much hampered by our ignorance of the peculiar influence of the earth’s rotation in any but the simplest cases. The importance of this element was first appreciated by Laplace, and he succeeded in obtaining solutions of various problems relating to a globe completely covered with water to a depth either uniform throughout, or at any rate variable only with latitude. His work has been extended by Kelvin, G. Darwin, and Hough. For an excellent summary, reference may be made to Lamb’s ‘Hydrodynamics,’ which includes also important original additions to the theory. But it must not be overlooked that a theory which supposes the globe to be completely covered with water has very little relation to our actual tides. Indeed, in practice, tidal prediction borrows nothing from Laplace’s theory, unless it be to look for tidal periods corresponding with those of the generating forces. And this correspondence, although perhaps first brought into prominence in connection with Laplace’s theory, is a general mechanical principle, not limited to hydrodynamics. If the theory of terrestrial tides is to advance, it can only be by discarding the imaginary globe completely covered with water and considering examples more nearly related to the facts, as was done in some degree by Young and Airy in their treatment of tides in canals. It is true that we are unlikely to obtain in this way more than very rough indications, but even such are at present lacking. I am told that opinions differ on so fundamental a question as whether the Atlantic tides are generated in the Atlantic or are derived from the Southern Ocean. Probably both sources contribute; but a better judgment, based on some sort of discussion on a priori principles, does not appear hopeless. In this connection, it is interesting to observe that a comparison of spring and neap tides shows that the moon is more effective relatively to the sun than would be expected from the ratio of the generating forces. This indicates some approach to synchronism with a natural free oscillation. That the approach is closest in the case of the moon indicates that free period is longer than those of the actual lunar and solar tides.

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