Rotation Of Moon Research Articles

Enigmatic Gravity Effects Observed during Solar Eclipses. Their Analyse by Quantum Model of Inertia and Gravitation

Foucault long pendulums, with spherical suspended mass, show Earth rotation by the constant velocity drift of their oscillation plane. Maurice Allais used a short, 84 centimeters pendulum, with a suspended bronze disc mass. He recorded its oscillation plane drift velocity, during solar eclipses, in 1954 and 1959. Both times, he noticed an anomalous drift of the oscillation plane. Several authors confirmed the effect, during next solar eclipses, with other types of pendulums. Then a group of Geophysicists, from the Science Academy of China, used an accurate digital gravimeter to measure Earth Gravity acceleration during March 09, 1997 solar eclipse. Their gravimeter recorded two drops of Earth Gravity acceleration (respectively 5.02 and 7.7 µ Gals) before and during first and last contacts of the Moon disc. However there was no acceleration drop during eclipse totality. Same phenomena were confirmed later, during next solar eclipses, with the same gravimeter. No classical causes for these facts were found, since modern gravimeters take care of temperature and atmospheric pressure variations. We analyse the effect of Moon rotation, and of solar Corona mass, in the frame of our Quantum model of Inertia and of Gravitation. The model predicts that Moon / Earth Gravity acceleration changes, when the Moon direction is close to the Sun one, as observed from the gravimeter place. That phenomenon should be tied to Quantum fluctuations dispersion by matter. Recorded measurements confirm that interpretation.

Local wisdom as a determinant of the season and wind calendar for coastal communities in Jaring Halus Village

The purpose of this research is to describe a local wisdom of jaring halus village coast communities, Secanggang District of Langkat Regency towards the determination of sea time and analysis based on the seasonal and wind calendars according to the experience of community adaptation. The method of this research is a qualitative descriptive by using the adaptation approach described by Steward in the framework of Cultural ecology analysis. The results of this study indicate that weather change is an important indicator of activity. Hence, by revealing the life cycle of the coastal community, it will be known also the general timeframe allocated for work. As a community whose life depends on the tidal cycle of the sea, the life of the fishing community on the East Coast of North Sumatra does make the moon's rotation of the earth as a basis for consideration in recognizing marine phenomena. the community believes that Knowledge of the Arabic calendar or hijri is proven relevant. The relevance is because of the Islamic calendar year calculated based on the circulation of the moon and the position of the moon astronomically that influence the conditions in the ocean. Seasonal changes in coastal and marine ecosystems are identical to the dates of the hijriyah year.

Augmented Reality Applied in Astronomy Subject

Mobile augmented reality is one of the most potential technology for education. Science astronomy is one of the subject that need to develop by mobile augmented reality technology. Purpose in this research is to create mobile augmented reality based on astronomy subject in Indonesian curriculum in junior high school. Animation that has been show in this application follows Kepler’s law about planetary motion. This research is R&D research and it follow instructional design type ADDIE. This researcher collected the data qualitatively from 2 experts, 2 teachers and 2 students. Each of participant will give suggestion to improve the quality of the application. Finally the application has been made with 16 marker. 11 explain about member of solar system, 3 marker about rotation and revolution of earth and moon, and 2 marker is about solar eclipse and moon eclipse. The application size is 47 Mb with Apk format. It can be use at least in android version 4.1 jelly bean and camera 13 MP. This application is ready to use for more large participant.

Предполагаемая концепция: вращение – метод существования Вселенной

In this concept, authors seek to prove that all planets revolve around their axes because of the impact of their satellites. The rotation of the joint gravitational force is similar for all planets and for the Sun. The Sun and each planet can have several satellites. The joint gravitational force of each pair – the satellite of the planet and the planet itself, the satellite of the Sun and the Sun itself, if the joint force of gravity, moves due to the motion of the satellite in orbit, rotates the planet or the Sun. The article proves that the joint gravity of the Moon and the Earth, which moves around the Earth due to the Moon's rotation around the Earth, rotates the Earth around its axis. And that the joint gravity of the Moon and Earth holds the Moon so that the side of the Moon with a larger mass is located in the direction of Earth. All satellites (there are more than 150 of them) are in the same rigid stable position – depending on their planets. And all the satellite planets in the solar system in rotation around their axes depend on their satellites. The Earth and the Moon in this matter are not original. Researchers provide evidence of the absence of a thermonuclear reaction on stars and the fact that the energy of solar radiation is electrical energy, not thermonuclear. In addition, the existence of dark matter is questioned in the work. The authors also prove that it is necessary to exclude the term "synchronization", which has no right to exist due to the absence of satellites rotation of the planets around their axes.

Analytical Theory Development Method for the Moon Rotation: Basic Laws in Its Movement

In the paper we deal with development of a high-precision and completely analytical theory of the Moon rotational motion, consider a mechanical system where the Moon and the Earth are non-spherical solids, and the Sun and planets are balls with concentric distributions of densities (or material points). The motion of the Moon's centre of mass is described by the improved theory of ILE (Improved Lunar Ephemeris). To develop the theory, we use specially developed methods and algorithms of conditionally periodic solutions of the Hamiltonian systems with complete resonance of basic frequencies and studying their neighbourhood. The apparatus of generalized (complex) representations of the strength functions of the problem and their expansions in Fourier series is used. The paper provides a brief rationale of the model problem under consideration, a choice of methods to study a physical libration of the Moon and a substantiation of basic laws in its motion. Estimates various perturbing factors, makes a choice of the small parameter, and reduces equations of the rotational motion of the Moon to the standard form of the Hamiltonian systems for which the algorithms for conditionally periodic solution and studying their neighbourhoods are developed. As a result of using the first of these algorithms, there is a generating periodic solution, which allows us to describe the basic laws in the Moon motion. Thus, the substantiation of Cassini's laws is given taking into complete account the appropriate orbital perturbations of the Moon, described by ILE theory. It is shown that desirable stability requirements for the perturbed rotational motion of the Moon in the vicinity of its periodic Cassini motion are met. This theory is of particular interest for the interpretation and scientific use of modern data resulted from the high-precision optical observations of the Moon performed from the Earth's surface as well as (in the future) for data processing of astrometry and optic observations carried out using the lunar research bases.

HISAB FALAK DAN RU'YAH HILAL (Antara Misi Ilmiah dan Seruan Ta’abbud)

Calculation of moon rotation and seeing crescent often give different result of the condition and position of the crescent. This makes many scholars have different opinion of the calculation of moon rotation and seeing crescent role in deciding the first date of Islamic month. Is only the calculation of moon rotation qualified? Or is only the seeing crescent qualified? Or the both are qualified? However, the opinion to using the both, even though the result is different, is better than using only one of them. It is because by using the both, the condition and position of the crescent can be made sure, so that the causal factor of different result can be certain. This article tries to promote to use the both in deciding the first date of Islamic month. The calculation of moon rotation is only an instrument to make sure that seeing crescent can be done accurately.

MRS2016: Rigid Moon Rotation Series in the Relativistic Approximation

Abstract The rigid Moon rotation problem is studied for the relativistic (kinematical) case, in which the geodetic perturbations in the Moon rotation are taken into account. As the result of this research the high-precision Moon Rotation Series MRS2016 in the relativistic approximation was constructed for the first time and the discrepancies between the high-precision numerical and the semi-analytical solutions of the rigid Moon rotation were investigated with respect to the fixed ecliptic of epoch J2000, by the numerical and analytical methods. The residuals between the numerical solution and MRS2016 in the perturbing terms of the physical librations do not exceed 80 mas and 10 arc seconds over 2000 and 6000 years, respectively.

Lunar recession encoded in tidal rhythmites: a selective overview with examples from Argentina

The study of tides from the sedimentary record of tidal rhythmites, applying fast Fourier transform analysis, contributes to the understanding of the surficial evolution of our highly dynamic planet, and of the astronomical cycles that influenced the ancient tidal systems. This overview of lunar retreat rates, which includes examples from Argentina, displays a generalized pattern of nonlinear, progressively extended lunar cycles up to the present day. The lunar retreat calculated at different stages of the Earth’s history identifies three time spans of extremely high recession rates, amounting to almost twice that of the present day: Archean–Paleoproterozoic (6.93 cm/year), Neoproterozoic I–Ediacaran (7.01 cm/year) and Ediacaran–early Cambrian (6.48 cm/year). Older comparable recession rates are difficult to recognize because of the lack of tidal rhythmic sequences. The maximum lunar retreat rate is registered after the Copernican meteor bombardment event on the Moon at ~900 Ma, and the time span coincides with the continental dispersal of Rodinia. Every acceleration of the lunar retreat rate coincides with two main processes: (1) meteorite impacts on the Earth or Moon, and (2) reconfiguration of landmasses accompanied by earthquakes that generated changes in the rotational axis of the Earth, inundation surfaces, and glaciation/deglaciation processes. The simultaneous occurrence of such processes makes it difficult to distinguish the causes and effects of each individual process, but its conjunction would have promoted the destabilization of the Earth–Moon system in terms of moment of inertia that was transferred to the Moon rotation.

Current problems of dynamics of moons of planets and binary asteroids based on observations

The general approach to studying the dynamics of moons of planets and asteroids consists in developing more and more accurate models of motion based on observational data. Not only the necessary ephemerides, but also some physical parameters of planets and moons are obtained this way. It is demonstrated in the present study that progress in this field is driven not only by the increase in accuracy of observations. The accuracy of ephemerides may be increased by expanding the observation time interval. Several problems arise on the way toward this goal. Some of them become apparent only when the procedure of observational data processing and use is examined in detail. The method used to derive astrometric data by processing the results of photometric observations of mutual occultations and eclipses of planetary moons is explained below. The primary contribution to the error of astrometric results is produced by the unaccounted noise level in photometric readings and the inaccuracy of received values of the albedo of moons. It is demonstrated that the current methods do not allow one to eliminate the noise completely. Extensive additional photometric measurements should be performed at different angles of rotation of moons and in different spectral bands of the visible wavelength range in order to obtain correct values of the albedo of moons. Many new distant moons of the major planets have been discovered in the early 21st century. However, the observations of these moons are scarce and were performed over short time intervals; as a result, some of the moons were lost. The necessity of further observations of these Solar System bodies is pointed out in the present study. Insufficient knowledge of asteroid masses is an obstacle to improving the accuracy of the ephemerides of Mars. The basic method for determining the masses of large asteroids consists in analyzing their influence on the motion of Mars, the Earth, and spacecraft. The masses of more than 100 large asteroids were determined this way. One of the principal techniques for Earth-based measurement of the masses of asteroids involves astrometric observations of binary asteroids. The determination of relative coordinates is made rather difficult by the apparent proximity of components. The success of these efforts depends on the availability of instrumentation and the expertise of observers skilled in adaptive optics and speckle interferometry. Collaboration between different research teams and observers is absolutely necessary.

Investigation of the Moon rotation in the relativistic approximation

Investigation of the Moon rotation in the relativistic approximation

Numerical simulation of the Moon's rotation in a rigorous relativistic framework

This paper describes a numerical simulation of the rigid rotation of the Moon in a relativistic framework. Following a resolution passed by the International Astronomical Union (IAU) in 2000, we construct a kinematically non-rotating reference system named the Selenocentric Celestial Reference System (SCRS) and give the time transformation between the Selenocentric Coordinate Time (TCS) and Barycentric Coordinate Time (TCB). The post-Newtonian equations of the Moon's rotation are written in the SCRS, and they are integrated numerically. We calculate the correction to the rotation of the Moon due to total relativistic torque which includes post-Newtonian and gravitomagnetic torques as well as geodetic precession. We find two dominant periods associated with this correction: 18.6yr and 80.1 yr. In addition, the precession of the rotating axes caused by fourth-degree and fifth-degree harmonics of the Moon is also analyzed, and we have found that the main periods of this precession are 27.3d, 2.9 yr, 18.6 yr and 80.1 yr.

Forced libration of tidally synchronized planets and moons

Tidal dissipation of kinetic energy, when it is strong enough, tends to synchronize the rotation of planets and moons with the mean orbital motion, or drive it into long-term stable spin-orbit resonances. As the orbital motion undergoes periodic acceleration due to a finite orbital eccentricity, the spin rate oscillates around the equilibrium mean value too, giving rise to the forced, or eccentricity-driven, librations. Both the shape and amplitude of forced librations of synchronous viscoelastic planets and moons are defined by a combination of two different types of perturbative torque, the tidal torque and the triaxial torque. Consequently, forced librations can be tidally dominated (e.g., Io and possibly Titan) or deformation-dominated (e.g., the Moon) depending on a set of orbital, rheological, and other physical parameters. With small eccentricities, for the former kind, the largest term in the libration angle can be minus cosine of the mean anomaly, whereas for the latter kind, it is minus sine of the mean anomaly. The shape and the amplitude of tidal forced librations determine the rate of orbital evolution of synchronous planets and moons, i.e., the rate of dissipative damping of semimajor axis and eccentricity. The known super-Earth exoplanets can exhibit both kinds of libration, or a mixture thereof, depending on, for example, the effective Maxwell time of their rigid mantles. Our approach can be extended to estimate the amplitudes of other libration harmonics, as well as the forced libration in non-synchronous spin-orbit resonances.

Precipitation Climatology on Titan-like Exomoons.

The availability of liquid water on the surface on Earth's continents in part relies on the precipitation of water. This implies that the habitability of exomoons has to consider not only the surface temperature and atmospheric pressure for the presence of liquid water, but also the global precipitation climatology. This study explores the sensitivity of the precipitation climatology of Titan-like exomoons to these moons' orbital configuration using a global climate model. The precipitation rate primarily depends on latitude and is sensitive to the planet's obliquity and the moon's rotation rate. On slowly rotating moons the precipitation shifts to higher latitudes as obliquity is increased, whereas on quickly rotating moons the latitudinal distribution does not strongly depend on obliquity. Stellar eclipse can cause a longitudinal variation in the mean surface temperature and surface pressure between the subplanetary and antiplanetary side if the planet's obliquity and the moon's orbital distance are small. In this particular condition the antiplanetary side generally receives more precipitation than the subplanetary side. However, precipitation on exomoons with dense atmospheres generally occurs at any longitude in contrast to tidally locked exoplanets.

Rers2014 and Mrs2014: New High-Precision Rigid Earth Rotation and Moon Rotation Series

Abstract Numerical investigation of the Earth and Moon rotational motion dynamics is carried out at a long time intervals. In our previous studies (Pashkevich, 2013), (Pashkevich and Eroshkin, 2011) the high-precision Rigid Earth Rotation Series (designated RERS2013) and Moon Rotation Series (designated MRS2011) were constructed. RERS2013 are dynamically adequate to the JPL DE422/LE422 (Folkner, 2011) ephemeris over 2000 and 6000 years and include about 4113 periodical terms (without attempt to estimate new subdiurnal and diurnal periodical terms). MRS2011 are dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 418, 2000 and 6000 years and include about 1520 periodical terms. In present research have been improved the Rigid Earth Rotation Series RERS2013 and Moon Rotation Series MRS2011, and as a result have been constructed the new high-precision Rigid Earth Rotation Series RERS2014 and Moon Rotation Series MRS2014 dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years, respectively. The elaboration of RERS2013 is carried out by means recalculation of sub-diurnal and diurnal periodical terms. The residuals in Euler angles between the numerical solution and RERS2014 do not surpass 3 ìas over 2000 years. Improve the accuracy of the series MRS2011 is obtained by using the JPL DE422/LE422 ephemeris. The residuals in the perturbing terms of the physical librations between the numerical solution and MRS2014 do not surpass 8 arc seconds over 6000 years

Phobos interior from librations determination using Doppler and star tracker measurements

Numerical simulations have been performed to assess the precision that can be obtained on Phobos libration angles by using two types of data acquired by a probe landed on the Martian moon: (1) Direct-To-Earth (DTE) Doppler data and (2) Star-Tracker (ST) data. Compared to independent estimates, combination of DTE and ST data provides the more precise estimates of Phobos libration angles at the 10−3−10−5 degree level. Short period libration amplitudes are functions of the relative moments of inertia. Thus their determination would provide constraints on mass distributions inside Phobos. We show that the longitudinal libration amplitude at the orbital period, while being clearly distinct from the resonance period, is the most interesting signal for that purpose, because it leads to the best precision on (B−A)/C (10−5 after only 10 weeks of operation). Nevertheless, we showed that inferring the individual moments of inertia A, B and C with a precision sufficient (<1%) to distinguish the rotational behavior of an homogenous from that of an heterogenous body requires the determination of one of the degree-two gravity field coefficient at the percent level.In addition, we stress that ST and DTE data combination allows de-correlating librational motion from orbital motion since ST measurements are sensitive to the moon's rotation and do not depend on its ephemeris, whereas DTE Doppler data are sensitive to both motions as well as to Phobos' surface displacement due to the tides raised by Mars. Furthermore, the ephemeris of Phobos has to be known at the centimeter level to allow measuring the tidal surface displacement with enough precision to conclude on the nature of Phobos' interior (rubble pile versus monolithic) as one step toward constraining its origin and evolution.

Origin and Evolution of the Moon

AbstractSince the Moon is the only natural satellite of the Earth, the research on the formation of the Moon can not only find out the formation mechanism of the satellites of Solar System planets but also reveal the evolution law of galaxies in the universe. Hence many hypotheses have been proposed for the Moon's formation, including fission,capture,condensation,and impact event hypothesis, but they all have problems. Recently, the author of this abstract discovered the formation mechanism of the Moon, which can be called “evolution theory”, and described as follows: During some violent volcanic eruptions of the Earth, some rock debris such as pumice through deep rock hole could achieve a velocity no less than the first cosmic velocity (7.9 km/s) to enter an orbit around the Earth, one of the biggest debris is the young Moon.The orbit of the young Moon might be much closer to the Earth than it is today. There were a lot of ejecta from the Earth in the space. Hence, the Moon has merged these ejecta to become larger and larger, and farther and farther away from the Earth.This can be proved as follows: When the Moon moved around the Earth normally, the centrifugal force produced by the Moon's rotation around the Earth and the Earth's gravitation pull on the Moon had the same size. Let M be the mass of the Earth, m1 be the mass of the Moon, rm be the radius of the Moon, r be the centroid distance between the Earth and the Moon, v be the tangential velocity of the Moon around the Earth, then Gm1M/r2=m1v2/r, therefore $v=\sqrt{GM/r}$. Near the orbit of the Moon, there were also many smaller prograde planetesimals moving around the Earth in circular orbits of radius rx(r–rm&lt;rx&lt;r) with velocity vx. Since $v_x=\sqrt{GM/r_x}&gt;\sqrt{GM/r}$, which implies vx &gt; v, these planetesimals would finally catch and merge with the Moon.Especially,if a planetesimals was large enough, it would impact the Moon forcefully, making the Moon's velocity increase to a larger value v2. Then m1v22/r&gt;m1v2/r=Gm1M/r2, therefore the Moon moved a reasonable distance away from the Earth.The early orbit of the Moon was much closer to the Earth's atmosphere than it is now, so the Moon had absorbed much water vapor from the atmosphere to form lunar maria. Due to the constant erosion of water,a series of volcanic eruptions occurred at the bottom of lunar maria.Violent eruption could also change the orbit of the Moon around the Earth. Since most maria are on the near-side visible from Earth, so many violent volcanic eruptions at the bottom of these lunar maria could push the moon away from the Earth. This can be proved as follows: Let M be the mass of the Earth, m1 be the mass of the Moon left by the volcanic eruption, m2 be the total mass of erupted matter, m0(=m1+m2) be the total mass of the Moon before the eruption, v be the tangential velocity of the Moon around the Earth, r0 and r1 be the centroid distance between the Earth and the Moon before or after the eruption respectively; since the volcano ejected many substances toward the Earth, r1 &gt; r0. Before the eruption, the centrifugal force produced by the Moon's rotation around the Earth and the Earth's gravitation pull on the Moon had the same size, therefore Gm0M/r02=m0v2/r0, which implies GM/r02=v2/r0. After the eruption,if the Moon hadn't changed its orbit then its velocity around the Earth was still v, so Gm1M/r12=(Gm1M/r02) (r02/r12)=(m1v2/r0) (r02/r12) =(m1v2/r1) (r0/r1)&lt;(m1v2/r1), adding the continuous giant reaction force produced by volcanic eruption, the join force could push the Moon away from the Earth, even to an orbit where the water vapor evaporated from the Moon would be attracted back to the Earth,leaving dry lunar maria.

Construction of the semi-analytical and numerical solutions to the problem of rotational motion of the moon

New high-precision, semianalytical and numerical solutions to the problem of the rotational motion of the Moon are obtained, for use in the long 418.9-year time frame. The dynamics of the rotational motion of the Moon is studied numerically using the Rodrigues-Hamilton parameters, relative to the fixed ecliptic for the epoch J2000. The results of the numerical solution to the problem under study are compared with a compiled semianalytical theory of Moon rotation (SMR). The initial conditions for the numerical integration have been taken from the SMR. The comparative discrepancies derived from the comparison between the numerical solutions and the SMR do not exceed 1.5″ on the time-scale of 418.9 yr. The investigation of the comparative discrepancies between the numerical and semianalytical solutions is performed using the least squares and spectral analysis methods in the Newtonian case. All the periodic terms describing the behavior of the comparative discrepancies are interpreted as the corrections to the semianalytical SMR theory. As a result, the series are constructed to describe the rotation of the Moon (MRS2010) in the time interval under study. The numerical solution for the Moon’s rotation has been obtained anew, with new initial conditions calculated using MRS2010. The discrepancies between the new numerical solution and MRS2010 do not exceed 20 arc milliseconds on the time-scale of 418.9 years. The results of the comparison suggest that that the MRS2010 series describe the rotation of the Moon more correctly than the SMR series.

Fuel near-optimal guidance law for the powered descending phase of a lunar module

This article proposes a fuel near-optimal robust guidance law for a lunar module during the powered descending phase in the lunar soft landing mission. At first, a three-dimensional kinetic model is introduced based on the defined target coordinate frame, where a single thruster misalignment and the moon rotation are considered. Next, with a computational method in conjunction with a time transform, a fuel optimal open-loop guidance law is derived for the nominal model without any disturbance. Then, to attenuate disturbances caused by thrust error and external disturbances, an additional robust H∞ feedback controller is designed to track the obtained reference trajectory and meet the constraints of control input, by solving a convex optimization problem with linear matrix inequality conditions. Finally, numerical simulation illustrates the effectiveness of the proposed approach.

An impact-driven dynamo for the early Moon

The origin of lunar magnetic anomalies remains unresolved after their discovery more than four decades ago. A commonly invoked hypothesis is that the Moon might once have possessed a thermally driven core dynamo, but this theory is problematical given the small size of the core and the required surface magnetic field strengths. An alternative hypothesis is that impact events might have amplified ambient fields near the antipodes of the largest basins, but many magnetic anomalies exist that are not associated with basin antipodes. Here we propose a new model for magnetic field generation, in which dynamo action comes from impact-induced changes in the Moon's rotation rate. Basin-forming impact events are energetic enough to have unlocked the Moon from synchronous rotation, and we demonstrate that the subsequent large-scale fluid flows in the core, excited by the tidal distortion of the core-mantle boundary, could have powered a lunar dynamo. Predicted surface magnetic field strengths are on the order of several microteslas, consistent with palaeomagnetic measurements, and the duration of these fields is sufficient to explain the central magnetic anomalies associated with several large impact basins.

Ancient lunar dynamo

The differential rotation between the Moon's core and mantle may have powered the ancient lunar dynamo, either continuously over several hundred million years or intermittently after large impacts. See Letters p.212 & p.215 Recent palaeomagnetic and seismological studies have strengthened the suggestion that the Moon once possessed a core dynamo. Despite its importance as a constraint on lunar evolution, there is currently no consensus on how such a dynamo was driven. Two groups working independently have arrived at the idea that the lunar dynamo was powered by mechanical stirring of the liquid core. Dwyer et al. investigate the mechanism of a dynamo driven by continuous mechanical stirring arising from the differential motion between the solid silicate mantle and the liquid core beneath. They show that the fluid motions and the power required to drive a dynamo operating continuously for more than 1 billion years are readily obtained by such mechanical stirring. Le Bars et al. propose a model whereby the dynamo action comes from impact-induced changes in the Moon's rotation rate. They show that basin-forming impact events are energetic enough to have unlocked the Moon from synchronous rotation, and that the subsequent large-scale fluid flows in the core, excited by the tidal distortion of the core–mantle boundary, could have powered a lunar dynamo.