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1.
The aim of this investigation is to present the secular and periodic perturbations of the six orbital elements of a close binary system due to rotational distortion. In our study we consider very small inclinationst of the orbital plane of the system, whereas the eccentricity of the orbit may assume any value between 0<e<1. The final formulae for the various elements have been expressed by means of the unperturbed true anomaly measured from the ascending node. 相似文献
2.
Basil Zafiropoulos 《Astrophysics and Space Science》1987,139(1):111-128
The equations for the variation of the osculating elements of a satellite moving in an axi-symmetric gravitational field are integrated to yield the complete first-order perturbations for the elements of the orbit. The expressions obtained include the effects produced by the second to eighth spherical harmonics. The orbital elements are presented in the most general form of summations by means of Hansen coefficients. Due to their general forms it is a simple matter to estimate the perturbations of any higher harmonic by simply increasing the index of summation. Finally, this paper gives the respective general expressions for the secular perturbations of the orbital elements. The formulae presented should be useful for the reductions of Earth-satellite observations and geopotential studies based on them.List of Symbols
semi-major axis
- C
jk
n
(, )
cosine functions of and
-
e
eccentricity of the orbit
-
f
acceleration vector of perturbing force
-
f
sin2t
- i
inclination of the orbit
-
J
n
coefficients in the potential expansion
-
M
mean anomaly
-
n
mean motion
-
p
semi-latus rectum of the orbit
-
R, S, andW
components of the perturbing acceleration
-
r
radius-vector of satellite
-
r
magnitude ofr
-
S
jk
n
(, )
sine functions of and
-
T
time of perigee passage
-
u
argument of latitude
-
U
gravitational potential
-
true anomaly
-
V
perturbing potential
-
G(M++m) (gravitational constant times the sum of the masses of Earth and satellite)
- n,k
coefficients ofR component of disturbing acceleration (funtions off)
- n,k
coefficients ofS andW components of disturbing acceleration (functions off)
-
mean anomaly at timet=0
-
X
0
n,m
zero-order Hansen coefficients
-
argument of perigee
-
right ascension of the ascending node 相似文献
3.
Twelve trace elements (antimony, arsenic, cadmium, chromium, cobalt, copper, iron, managenese, mercury, scandium, selenium and zinc) were determined by neutron activation analysis in a planktonic copepod (Acartia clausi) from Elefsis Bay of the Upper Saronikos Gulf, Greece. During the first cruise (January 1974) higher levels of most of these trace elements were found in this copepod collected from a polluted area of the bay. This trend however was not observed during the second cruise (February 1974) possibly due to the termination of the active vertical convection. Lower levels of cobalt, similar levels of iron and slightly increased levels of chromium were found in Elefsis Bay Acartia clausi from those reportedin Acartia clausi from the Bay of Roquebrune. Slightly increased concentrations of antimony and zinc as well as lower concentrations of arsenic and cadmium were found in Acartia clausi than those reported in other Copepoda. No significant differences were found for copper, manganese and mercury. More data are needed to confirm if higher levels of antimony, chromium and zinc found in Acartia clausi are due to the pollution of the bay. 相似文献
4.
G. Papakostidis A.P. Grimanis D. Zafiropoulos G.B. Griggs T.S. Hopkins 《Marine pollution bulletin》1975,6(9):136-139
Sediments in the upper Saronikos Gulf have been contaminated by heavy metals from the discharge of untreated industrial and domestic wastewater from the area around Athens. Neutron activation analysis indicates concentrations of antimony, arsenic, chromium, gold, mercury, silver and zinc are 8–200 times greater than in the surrounding uncontaminated sediments. The bottom area affected by increased metal concentrations is at least 13 km2 and indicates a nearly radial dispersal pattern from the main outfall with higher concentrations extending to the southeast and southwest. 相似文献
5.
B. Zafiropoulos 《Astrophysics and Space Science》1987,137(1):139-149
The aim of this investigation is to present the periodic and secular perturbations of the orbital elements of close binary systems due to tidal lag in latitude. The variational equations of the problem of plane motion will be set up in terms of the rectengular componentsR, S, andW of the disturbing accelerations. These equations are highly nonlinear with respect to the orbital elements and we present analytic approximations to the effects produced by the perturbing acceleration due to dynamical tides lagging in latitude. The perturbed elements of the orbit have been expressed by means of Hansen coefficients in the compact form of summations. 相似文献
6.
B. Zafiropoulos 《Astrophysics and Space Science》1987,136(1):149-165
This paper deals with the perturbations which tidal lag in longitude can produce to the orbital elements of a close binary system. The expressions obtained for the six elements of the orbit have been presented as functions of the unperturbed true anomaly, measured from the periastron. Our study includes the effects produced by the second, third, and fourth tidal harmonic distortions. In order to save space these extremely lengthy equations are given in the compact form of summations, by means of Hansen coefficients. Various recurrence relations, which hold good for Hansen coefficients, are also presented. Finally, this paper includes a second-order approximation only for the secular terms of first-order approximation. 相似文献
7.
In two previous papers (Zafiropoulos and Kopal, 1983a, b; hereafter referred to as Papers I and II) we have investigated the effects of rotational and tidal distortion (for non-lagging tides) on the orbital elements of a close binary system. The present paper deals with secular and periodic perturbations caused by dynamical tides. The componentsR, S, andW of disturbing accelerations for tidal lag have been substituted in the Gaussian form of Lagrange's planetary equations to give the first-order approximation. The results obtained have been expressed by means of Hansen coefficients and include the effects produced by the second, third and fourth harmonic dynamical tides. 相似文献
8.
In a previous paper (Zafiropoulos and Kopal, 1982; hereafter referred to as Paper I) we have studies the effects of rotational distortion on the orbital elements. The aim of the present paper is to investigate the secular and periodic perturbations of the orbital elements due to tidal distortion. For tidal distortion when tides do not lag, the Gaussian form of Lagrange's planetary equations has been employed to yield the first- and second-order approximations. The results obtained include the effects produced by the second, third and fourth harmonic distortions. The first order approximation for non-lagging tides has been expressed by means of Hansen coefficients. 相似文献
9.
L. Tositti M. Mingozzi S. Sandrini L. Forlani M.C. Buoso M. De Poli D. Ceccato D. Zafiropoulos 《Global and Planetary Change》2006,53(4):278
Two peat columns from Tunguska (Siberia) were analysed for pollen, spores, charcoal, trace elements and γ-emitters in order to identify the fingerprints of the impact of a still unidentified cosmic body (TCB), which occurred in the summer of 1908, and the level of environmental pollution in a background area of central Siberia. Peat layers were subject to non-destructive γ-ray spectrometry to derive radiochronology by the excess 210Pb method. The age-to-depth relationship was crosschecked by using both 1963 horizon of 137Cs associated to maximum global fallout deposition and palynological data profiles. Vertical distributions of trace elements in the peat columns were obtained by PIXE multielemental analysis allowing determination of the levels of environmental contamination in a background region of the Siberian taiga.The association of heavy metals such as Ni, Co and Cu in the profiles suggests the connection of the area with mining and metal smelting activity in the north of the region through atmospheric circulation. As concerns global scale contamination, the inventory of the artificial radionuclide 137Cs (4.6 kBq m− 2) shows a value typical of remote slightly contaminated areas resulting from global scale redistribution of radioactive fallout from Cold War nuclear weapon testing. The atmospheric inventory of the natural radionuclide 210Pb, for which a mean annual flux of 200 Bq m− 2 yr− 1 has been calculated, is typical of continental regions.The influence of Tunguska Cosmic Body in the peat is recognizable by a large discontinuity in the palynological profile of the peat monolith at a depth coinciding with the 1908 layer as determined by the 210Pb technique, showing a large peak of total pollen counting attributed to the impact of the shockwave on the area in which huge tree stands were destroyed. Following the event, tree pollen concentration decreases abruptly showing the temporary inception of a mire environment with an increase of Sphagnum spore concentrations. Results of elemental analysis so far available do not show anomalies in the concentration profiles at depths coinciding with the Tunguska event layer indicating the need for pre-concentration technique enabling the detection of element associations typical of extraterrestrial materials. 相似文献
10.
Christophe Clment Maria Sachpazi Philippe Charvis David Graindorge Mireille Laigle Alfred Hirn Giorgios Zafiropoulos 《Tectonophysics》2004,391(1-4):97
The Gulf of Corinth is a natural laboratory for the study of seismicity and crustal deformation during continental extension. Seismic profiling along its axis provides a 24-fold normal-incidence seismic reflection profile and wide-angle reflection–refraction profiles recorded by sea-bottom seismometers (OBS) and land seismometers. At wide-angle incidence, the land receivers document the Moho at 40-km depth under the western end of the Gulf north of Aigion, rising to 32-km depth under the northern coast in the east of the Gulf. Both refraction and normal-incidence reflection sections image the basement under the deep marine basin that has formed by recent extension. The depth to the base of the sedimentary basin beneath the Gulf, constrained by both methods, is no more than 2.7 km, with 1 km of water underlain by no more than 1.7 km of sediment, less than what was expected from past modeling of uplift of the south coast in the East of the Gulf. Unlike the flat sea-bottom, the basement and sedimentary interfaces show topography along this axial line. Several deeps are identified as depocenters, which suggest that this axial line is not a strike line to the basin. It appears instead to be controlled by several faults, oblique to the S60°E overall trend of the south coast of the Gulf, their more easterly strikes being consistent with the instantaneous direction of extension measured by earthquake slip vectors and by GPS. 相似文献