Related papers: The Chandler wobble and Solar day
In this paper, in the first instance the attitude dynamics of the Earth is modelled based on physical principles so as to correctly predict the Chandler wobble and its features such as its period. To this end not only the steady state and…
We propose a model of the Earth's torqueless precession, the "Chandler wobble", as a self-oscillation driven by positive feedback between the wobble and the centrifugal deformation of the portion of the Earth's mass contained in circulating…
The Chandler wobble (CW) -- the $\sim$433-day free nutation of Earth's rotation pole -- experienced an anomalous near-disappearance between 2015 and 2020, followed by a re-excitation with an approximately $180^{\circ}$ phase reversal. Using…
Chandler wobble excitation and damping, one of the open problems in geophysics, is treated as a consequence in part of the interaction between Earth and a hypothetical oblate ellipsoid made of dark matter. The physical and geometrical…
The use of the Van Cittert--Zernike theorem for the formulation of the visibility function in satellite-based Earth observation with passive radiometers does not take into account the relative motion of the observer (the satellite antenna)…
Five Venus missions are under development to study the planet in the next decade, with both NASA's VERITAS and ESA's EnVision featuring a geophysical investigation among their objectives. Their radar and gravity experiments will determine…
In the last two decades an anomalous variation in the asymptotic velocity of spacecraft performing a flyby manoeuvre around Earth has been discovered through careful Doppler tracking and orbital analysis. No viable hypothesis for a…
We study the scintillation produced by time-varying gravitational fields within scalar-tensor theories of gravity. The problem is treated in the geometrical optics approximation for a very distant light source emitting quasi plane…
Standard treatments of general relativity accept the gravitational slowing of clocks as a primary phenomenon, requiring no further analysis as to cause. Rejecting this attitude, I argue that one or more of the fundamental "constants"…
Motivated by inclination of the Earth's orbit that is not located at galactic plane for observing the shadow of Sgr A*, we consider the black hole shadow for arbitrary inclinations and different velocities of observers. A surprising finding…
Solar-Limb Effect is an observational phenomena connected to the solar gravitational red-shift. It shows a variation of the magnitude of the gravitational red-shift from the center to the limb of the solar disc. In the present work an…
The orbital displacement of the Moon is known to a precision on the order of centimeters from the lunar laser ranging data, while the lunar profile's confidence level is still only about 200 m. The lunar motion is used to measure the solar…
General Relativity (GR) is shown to be a complete theory with respect to the isochrony of the pendulum. This guarantees that time can be measured with a mechanical clock within the theory itself as a matter of principle. The proper and…
In this work, the nutation momentum acting upon the Earth from the Moon's perigee mass that has not been taken into account in the Earth's precession-nutation theory was revealed. This missing momentum exhibits itself in the so-called…
We determine here peculiar motion of the Solar system, first time from the $m-z$ Hubble diagram of quasars. Observer's peculiar motion causes a systematic shift in the $m-z$ plane between sources lying along the velocity vector and those in…
Space-time covariance modeling under the Lagrangian framework has been especially popular to study atmospheric phenomena in the presence of transport effects, such as prevailing winds or ocean currents, which are incompatible with the…
Earth rotation is one of astronomical phenomena without which it is impossible to think of human life. That is why the investigation on the Earth rotation is very important and it has a long history of study. Invention of quartz clocks in…
In this article we discuss some aspects of solar physics from the standpoint of the so-called chameleon fields (i.e. quantum fields, typically scalar, where the mass is an increasing function of the matter density of the environment).…
The nearly-incessant free oscillations of the Earth (not the larger, long-lived normal modes seen following intense quakes) were first observed by accident in the record of a tilt-sensitive instrument designed to study surface physics.…
The dominant CMB dipole anisotropy is a Doppler effect due to a particular motion of the solar system with velocity of 370 km/s. Since this derives from peculiar motions and local inhomogeneities, one could meaningfully consider a…