II.—“The Origin of Mountains”: a Reply

1913 ◽  
Vol 10 (10) ◽  
pp. 434-435
Author(s):  
Rev. O. Fisher
Keyword(s):  
Rotation Velocity ◽  
Earth’S Rotation ◽  
The Moon ◽  
The Earth ◽  
Low Latitudes ◽  
Rotation Of The Earth ◽  
External Forces ◽  
Dense Liquid ◽  
Do So ◽  
Geological Magazine

I am content to leave to the readers of the Geological Magazine the question whether Colonel Burrard's theory of the elevation of mountains and Mr. Hayford's of the distribution of density to cause isostasy are more in accordance with geological phenomena than my theory of mountain roots supported in a dense liquid substratum. But in Colonel Burrard's reply to my paper in the Magazine for June there is a fundamental but specious error. I wrote: “Is it not possible that the earth's rotation may impart to it a ‘gyroscopic’ quasi rigidity, which may enable it to withstand the deforming influence of external forces [the attraction of the moon and sun], although at the same time forces internal to the earth will be unaffected by it.” To this Colonel Burrard replies: ”Mr. Fisher has argued that the rotation of the earth will give to the liquid interior an effective rigidity; but this rotation has conferred no rigidity upon our oceans, and even if it did render the liquid interior rigid, it would only do so in low latitudes where the rotation velocity is high. I understand, moreover, that the earth's interior was assumed by Mr. Fisher to be liquid, in order to explain the floatation of the crust. If the liquid is now proved to be rigid, the crust cannot be floating upon it.”

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 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 Specific Formation of the Bermuda and Dragon Triangles as a Result of a Change in the Axis of the Earth’s Rotation

2020 ◽  
pp. 19-25
Keyword(s):  
South America ◽  
Southeast Asia ◽  
Earth’S Rotation ◽  
Earth's Rotation ◽  
Axis Of Rotation ◽  
The Earth ◽  
Rotation Of The Earth ◽  
North And South America ◽  
North And South

The Bermuda Triangle is located in the area of the archipelago between North and South America and the Dragon Triangle is located in the area of the archipelago in Southeast Asia. There is a great resemblance between these two triangular areas; both were formed following special geological and tectonic conditions. It is herein proposed that their creation stems from the change in location of the axis of rotation of the earth and, accordingly, the change in the location of the equator.

Addendum 2020 to ‘Measurement of the Earth’s rotation: 720 BC to AD 2015’

2021 ◽  
Vol 477 (2246) ◽  
pp. 20200776
Author(s):  
L. V. Morrison ◽  
F. R. Stephenson ◽  
C. Y. Hohenkerk ◽  
M. Zawilski
Keyword(s):  
Angular Momentum ◽  
Earth’S Rotation ◽  
The Sun ◽  
Earth's Rotation ◽  
Moon System ◽  
Link Type ◽  
The Earth ◽  
Solar Eclipses ◽  
Rotation Of The Earth

Historical reports of solar eclipses are added to our previous dataset (Stephenson et al. 2016 Proc. R. Soc. A 472 , 20160404 ( doi:10.1098/rspa.2016.0404 )) in order to refine our determination of centennial and longer-term changes since 720 BC in the rate of rotation of the Earth. The revised observed deceleration is −4.59 ± 0.08 × 10 −22  rad s −2 . By comparison the predicted tidal deceleration based on the conservation of angular momentum in the Sun–Earth–Moon system is −6.39 ± 0.03 × 10 −22  rad s −2 . These signify a mean accelerative component of +1.8 ± 0.1 × 10 −22  rad s −2 . There is also evidence of an oscillatory variation in the rate with a period of about 14 centuries.

scholarly journals Basic Problems in the Kinematics of the Rotation of the Earth

1979 ◽  
Vol 82 ◽  
pp. 7-18 ◽  
Author(s):  
Bernard Guinot
Keyword(s):  
Earth Rotation ◽  
Rotation Axis ◽  
Earth’S Rotation ◽  
International Astronomical Union ◽  
Earth's Rotation ◽  
The Earth ◽  
International Astronomical ◽  
Rotation Of The Earth

With the advent of more precise methods for measuring Earth rotation, a number of corrections to the apparent directions in space, to the terrestrial references, and to the rotation axis motion have to be carefully applied. It is the duty of the international Astronomical Union to give recommended or conventional expressions of these corrections in order to avoid inextricable difficulties in discussing the evaluated results. However, this task is not sufficient. The concepts used in the description of the Earth's rotation are somewhat obscured by traditions. They should be purified by removing notions which are not directly relevant.

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.

Long-term changes in the rotation of the Earth : 700 B.C. to A.D. 1980

1984 ◽  
Vol 313 (1524) ◽  
pp. 47-70 ◽  
Keyword(s):  
Earth’S Rotation ◽  
Earth's Rotation ◽  
Temporal Behaviour ◽  
Tidal Friction ◽  
The Past ◽  
The Earth ◽  
Tidal Changes ◽  
Rotation Of The Earth ◽  
Tidal Variations

Occultations of stars by the Moon, and solar and lunar eclipses are analysed for variations in the Earth’s rotation over the past 2700 years. Although tidal braking provides the dominant, long-term torque, it is found that the rate of rotation does not decrease uniformly as would be expected if tidal friction were the only mechanism affecting the Earth’s rotation. There are also non-tidal changes present that vary on timescales ranging from decades to millennia. The magnitudinal and temporal behaviour of these non-tidal variations are evaluated in this paper.

scholarly journals VI.—The Geological Chronometer

1903 ◽  
Vol 10 (3) ◽  
pp. 122-127
Author(s):  
G. W. Bulman
Keyword(s):  
A Priori ◽  
The Earth ◽  
Equal Thickness ◽  
Do So ◽  
Geological Magazine

The pleasant relations normally existing among geologists, biologists, and physicists have of late become a trifle strained on the question of the age of the earth. Biologists, having failed to induce either geologists or physicists to draw sufficiently large cheques on the bank of time, have taken to signing the same them-selves, adding the ciphers ad lib. Professor Poulton has ably championed the rights of the biologists to do so, and in the course of his argument he contends that there is evidence in the sedimentary strata to show that their rate of formation was not greater than that at which deposits are now being accumulated.So far as I am aware, Professor Poulton's contention has not been either controverted or supported by any geologist. Hence it seems to be a suitable subject for discussion in the Geological Magazine.In the first place, then, what would be the nature of the evidence we might a priori expect to find to show that one set of beds was accumulated in a shorter time than another of equal thickness ? Would there, in fact, be any difference such as would enable us positively to decide the question ?Secondly, we may examine and compare rocks which we know, or have reason to suppose, have been formed at different rates. Now, according to Sir A. Geikie, if the rocks of the stratified systems were laid down at the greatest rate suggested by the facts of denudation. 73,000,000 years would be required; if at the least, 680,000,000.

The Use of Satnav Systems for Precise Time Transfer

1984 ◽  
Vol 37 (3) ◽  
pp. 348-353
Author(s):  
J. D. H. Pilkington
Keyword(s):  
Time Transfer ◽  
Daylight Saving Time ◽  
Daylight Saving ◽  
The Earth ◽  
The Status ◽  
Rotation Of The Earth ◽  
Economic Necessity ◽  
Precise Time ◽  
Do So

Everyone needs a knowledge of ‘the time’, even if the accuracy required is only sufficient to keep an appointment, catch a train or watch a particular TV programme. An isolated clock, started at random and ticking at an unknown rate, can only be used to compare intervals of time. Although this is often useful – for example, in cookery or athletics – the full value of a clock can be realized only if its reading provides a model of the status of a continuing process (such as the rotation of the Earth) or if the clock is a member of a group of clocks, all of which show the same time and may be expected to continue to do so. Particular applications may demand that some members of the group must be kept in closer agreement than others, or must all reliably remain within a stated tolerance for a longer period, but specifications of this kind arise only from economic necessity; in principle all clocks should agree at all times – subject, of course to the unavoidable restrictions imposed by the laws of physics and perhaps the complexities of daylight-saving time.

scholarly journals Rotation of the Rigid Earth

1997 ◽  
Vol 165 ◽  
pp. 295-300
Author(s):  
P. Bretagnon
Keyword(s):  
Time Domain ◽  
Time Span ◽  
Euler Angles ◽  
The Sun ◽  
The Moon ◽  
The Earth ◽  
Rigid Earth ◽  
The Time Domain ◽  
Tesseral Harmonics ◽  
External Forces

AbstractWe present the results of a solution of the Earth’s rotation built with analytical solutions of the planets and of the Moon’s motion. We take into account the influence of the Moon, the Sun and all the planets on the potential of the Earth for the zonal harmonics Cj,0 for j from 2 to 5, and also for the tesseral harmonics C2,2, S2,2C3,k, S3,k for k from 1 to 3 and C4,1, S4,1. We determine three Euler angles ψ, ω, and φ by calculating the components of the torque of the external forces with respect to the geocenter in the case of the rigid Earth. The analytical solution of the precession-nutation has been compared to a numerical integration over the time span 1900–2050. The differences do not exceed 16 μas for ψ and 8 μas for ω whereas the contribution of the tesseral harmonics reaches 150 μas in the time domain.

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