scholarly journals Features of the orbital motion control of geostationary satellites in the conditions of their collocation

2019 ◽  
Author(s):  
Yu.G. Sukhoy ◽  
V.F. Braginets ◽  
V.M. Mescheryakov
Keyword(s):  
Motion Control ◽  
Orbital Motion ◽  
Satellite Orbit ◽  
Orbital Parameter ◽  
The Sun ◽  
The Moon ◽  
Geostationary Satellites ◽  
The Given ◽  
Direction Opposite ◽  
Rational Direction

The article describes the analysis of features of safe orbital motion control for two geostationary satellites in one orbital zone. Under the given assumptions and limitations, the methods of controlling the satellite orbit eccentricities and inclinations by means of corrections, ensuring the implementation of the I-E-collocation method, are investigated. The result of research is the development of rational strategies for controlling the orbit eccentricities and inclinations of two satellites. The strategy of controlling eccentricity is a modification of the sun pointing perigee strategy and is called the quasi-sun pointing perigee strategy. The strategy of controlling inclinations takes into account the evolution of the orbital inclinations under the influence of the gravitational potentials of the Sun and the Moon in certain periods of the year and at different positions of the Moon orbit line of nodes. The developed strategies provide for reducing the fuel cost for the orbital parameter corrections at collocation of two satellites since eccentricity corrections are partially combined with corrections of satellite hold in longitude, and inclination corrections are performed in the most rational direction opposite to the direction of inclination vector growth

Index to Volume 277

1975 ◽  
Vol 277 (1274) ◽  
pp. 649-649
Keyword(s):  
Orbital Motion ◽  
Lunar Orbit ◽  
Artificial Satellites ◽  
Time Interval ◽  
The Sun ◽  
The Moon ◽  
Slight Effect ◽  
The Earth ◽  
Westerly Direction ◽  
Complete Revolution

Dr R. R. Newton has notified the following correction to his contribution. The paragraph at the bottom of page 16 and the top of page 17 should read: The node of the lunar orbit rotates in a westerly direction around the plane of the ecliptic, making a complete revolution in about 18.61 years. This motion, and this time interval, are important in eclipse theory, as we shall discuss in the next section. This motion results almost entirely from the perturbation of the Sun’s gravitation on the Moon’s orbital motion. The Earth’s equatorial bulge, which is almost entirely responsible for the motion of the nodes of artificial satellites near the Earth, has only a slight effect on a satellite as distant as the Moon.

scholarly journals Theory of the Libration of the Moon

1983 ◽  
Vol 74 ◽  
pp. 37-37
Author(s):  
M. Dubois-Moons
Keyword(s):  
Gravity Field ◽  
Orbital Motion ◽  
Lunar Theory ◽  
The Sun ◽  
Lunar Gravity ◽  
The Moon ◽  
Fourth Degree ◽  
Lunar Gravity Field ◽  
The Earth ◽  
Second Degree

AbstractThe paper presents a new theory of the libration of the Moon, completely analytical with respect to the harmonic coefficients of the lunar gravity field. This field is represented through its fourth degree harmonics for the torque due to the Earth (the second degree for the torque due to the Sun). The Moon is assumed to be rigid and its orbital motion is described by the ELP 2000 solution (Chapront and Chapront-Touzé 1981) for the main problem of lunar theory with planetary perturbations and influence of the non-sphericity of the Earth. Comparisons with other theories (Migus 1980 and Eckhardt 1981) are also presented.

scholarly journals Calculation Of Position And Velocity Of GLONASS Satellite Based On Analytical Theory Of Motion

2015 ◽  
Vol 50 (3) ◽  
pp. 105-114
Author(s):  
W. Góral ◽  
B. Skorupa
Keyword(s):  
Position Vector ◽  
The Sun ◽  
The Moon ◽  
Orbital Elements ◽  
Theory Of Motion ◽  
Analytical Algorithm ◽  
Glonass Satellite ◽  
The Given ◽  
Analytical Expressions ◽  
Interesting Alternative

Abstract The presented algorithms of computation of orbital elements and positions of GLONASS satellites are based on the asymmetric variant of the generalized problem of two fixed centers. The analytical algorithm embraces the disturbing acceleration due to the second J2 and third J3 coefficients, and partially fourth zonal harmonics in the expansion of the Earth’s gravitational potential. Other main disturbing accelerations – due to the Moon and the Sun attraction – are also computed analytically, where the geocentric position vector of the Moon and the Sun are obtained by evaluating known analytical expressions for their motion. The given numerical examples show that the proposed analytical method for computation of position and velocity of GLONASS satellites can be an interesting alternative for presently used numerical methods.

Modelling Lunar Extremes

2018 ◽  
Vol 3 (2) ◽  
pp. 207-216 ◽  
Author(s):  
David Fisher ◽  
Lionel Sims
Keyword(s):  
High Precision ◽  
Celestial Mechanics ◽  
Computer Modelling ◽  
Landscape Context ◽  
The Sun ◽  
The Moon

Claims first made over half a century ago that certain prehistoric monuments utilised high-precision alignments on the horizon risings and settings of the Sun and the Moon have recently resurfaced. While archaeoastronomy early on retreated from these claims, as a way to preserve the discipline in an academic boundary dispute, it did so without a rigorous examination of Thom’s concept of a “lunar standstill”. Gough’s uncritical resurrection of Thom’s usage of the term provides a long-overdue opportunity for the discipline to correct this slippage. Gough (2013), in keeping with Thom (1971), claims that certain standing stones and short stone rows point to distant horizon features which allow high-precision alignments on the risings and settings of the Sun and the Moon dating from about 1700 BC. To assist archaeoastronomy in breaking out of its interpretive rut and from “going round in circles” (Ruggles 2011), this paper evaluates the validity of this claim. Through computer modelling, the celestial mechanics of horizon alignments are here explored in their landscape context with a view to testing the very possibility of high-precision alignments to the lunar extremes. It is found that, due to the motion of the Moon on the horizon, only low-precision alignments are feasible, which would seem to indicate that the properties of lunar standstills could not have included high-precision markers for prehistoric megalith builders.

scholarly journals Solar barycentric dynamics from a new solar-planetary ephemeris

2018 ◽  
Vol 615 ◽  
pp. A153 ◽  
Author(s):  
Rodolfo G. Cionco ◽  
Dmitry A. Pavlov
Keyword(s):  
High Precision ◽  
Orbital Motion ◽  
Giant Planets ◽  
Reference Plane ◽  
The Sun ◽  
The Future ◽  
Dynamical Parameters ◽  
Definition Of ◽  
Invariable Plane ◽  
Planetary Theories

Aims. The barycentric dynamics of the Sun has increasingly been attracting the attention of researchers from several fields, due to the idea that interactions between the Sun’s orbital motion and solar internal functioning could be possible. Existing high-precision ephemerides that have been used for that purpose do not include the effects of trans-Neptunian bodies, which cause a significant offset in the definition of the solar system’s barycentre. In addition, the majority of the dynamical parameters of the solar barycentric orbit are not routinely calculated according to these ephemerides or are not publicly available. Methods. We developed a special version of the IAA RAS lunar–solar–planetary ephemerides, EPM2017H, to cover the whole Holocene and 1 kyr into the future. We studied the basic and derived (e.g., orbital torque) barycentric dynamical quantities of the Sun for that time span. A harmonic analysis (which involves an application of VSOP2013 and TOP2013 planetary theories) was performed on these parameters to obtain a physics-based interpretation of the main periodicities present in the solar barycentric movement. Results. We present a high-precision solar barycentric orbit and derived dynamical parameters (using the solar system’s invariable plane as the reference plane), widely accessible for the whole Holocene and 1 kyr in the future. Several particularities and barycentric phenomena are presented and explained on dynamical bases. A comparison with the Jet Propulsion Laboratory DE431 ephemeris, whose main differences arise from the modelling of trans-Neptunian bodies, shows significant discrepancies in several parameters (i.e., not only limited to angular elements) related to the solar barycentric dynamics. In addition, we identify the main periodicities of the Sun’s barycentric movement and the main giant planets perturbations related to them.

Sweat of the Sun and Tears of the Moon. Gold and Silver in Pre-Columbian Art

1967 ◽  
Vol 71 (2) ◽  
pp. 215
Author(s):  
Earle R. Caley ◽  
Andre Emmerich
Keyword(s):  
The Sun ◽  
The Moon
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