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991.
S. H. Zisk C. A. Hodges H. J. Moore R. W. Shorthill T. W. Thompson E. A. Whitaker D. E. Wilhelms 《Earth, Moon, and Planets》1977,17(1):59-99
The region including the Aristarchus Plateau and Montes Harbinger is probably the most diverse, geologically, of any area of comparble size on the Moon. This part of the northwest quadrant of the lunar near side includes unique dark mantling material; both the densest concentration and the largest of the sinuous rilles; apparent volcanic vents, sinks, and domes; mare materials of various ages and colors; one of the freshest large craters (Aristarchus) with ejecta having unique colors and albedos; and three other large craters in different states of flooding and degradation (krieger, Herodotus, and Prinz). The three best-authenticated lunar transient phenomena were also observed here.This study is based principally on photographic and remote sensing observations made from Earth and Apollo orbiting space craft. Results include (1) delineation of geologic map units and their stratigraphic relationships; (2) discussion of the complex interrelationships between materials of volcanic and impact origin, including the effects of excavation, redistribution and mixing of previously deposited materials by younger impact craters; (3) deduction of physical and chemical properties of certain of the geologic units, based on both the remote-sensing information and on extrapolation of Apollo data to this area; and (4) development of a detailed geologic history of the region, outlining the probable sequence of events that resulted in its present appearance.A primary concern of the investigation has been anomalous red dark mantle on the Plateau. Based on an integration of Earth- and lunar orbit-based data, this layer seems to consist of fine-grained, block-free material containing a relatively large fraction of orange glass. It is probably of pyroclastic origin, laid down at some time during the Imbrian period of mare flooding. 相似文献
992.
G. M. Tovmasyan R. Kh. Oganesyan R. A. Epremyan S. E. Nersesyan M. A. Mkrtchyan Yu. M. Khodzhayants M. N. Krmoyan A. L. Kashin D. Huguenin S. I. Serova Yu. V. Romanenko A. P. Aleksandrov V. G. Titov M. Kh. Manarov 《Astrophysics》1990,32(1):1-5
Byurakan Astrophysical Observatory; SKB Granit; Geneva Observatory; Flight Control Center. Translated from Astrofizika, Vol. 32, No. 1, p. 5–13, January–February, 1990. 相似文献
993.
We have applied a technique recently proposed basing on learning nonlinear dynamics locally to describe the annual sunspot relative numbers. It is proved that the number of past points for prediction should be greater than 4 but less than 10. This rather simple approach yields in average relatively good results for short-term forecasts (< 11 yr). Particularly, it predicts that the current cycle no. 22 will reach a very high maximum. However, this approach must be modified in the vicinity of a grand minimum. 相似文献
994.
Mutual Potential of Homogeneous Polyhedra 总被引:2,自引:0,他引:2
Robert A. Werner Daniel J. Scheeres 《Celestial Mechanics and Dynamical Astronomy》2005,91(3-4):337-349
The mutual gravitational potential between a pair of homogeneous polyhedra is expressed using an infinite series. The nested
volume integrals are evaluated analytically and result in simple tensor expressions containing no special functions. However,
complexity increases as O(6
n
), where n is the term degree. An alternate formulation due to Liebenthal is also presented. 相似文献
995.
Martin P. Kirkbride Margaret A. Bradshaw Fraka J. Harmsen 《Meteoritics & planetary science》1991,26(3):213-216
Abstract— Nine additional iron meteorite fragments weighing a total of 72 kg were recovered from the Derrick Peak area by a Canterbury Museum geological party in late 1988. One iron was located in the Onnum Valley, 6 km south of the previous finds. Geochemical analysis indicates that all irons belong to a single meteorite shower, greatly increasing the known extent of the fall zone. Kamp and Lowe (1982) have previously estimated the terrestrial age of the meteorite from glacial geological evidence. The location of the 1988 finds supports Kamp and Lowe's interpretation that the meteorites lie in situ, but recent revisions of the chronology of Cenozoic glacial history of the region reduce the interpreted terrestrial age. An age of between Oxygen Isotope stages 6 and 2 is probable (190–125 to 35–12 ka BP). This conflicts with a terrestrial age estimate of 1.0 ± 0.1 Ma BP from cosmogenic radionuclides. 相似文献
996.
997.
V. A. Kalmykov 《Physical Oceanography》1996,7(2):91-97
Zakharov's equation is applied to study numerically the evolution of wave amplitudes. It is demonstrated that, owing to Krasitskii's
new kernel functions, the system of surface waves remains Hamiltonian, in contrast to the former approaches used by Yuen,
Lake, and Zakharov. If surface waves are wind-generated, they grow and become stochastic. If the effect of the waves on the
wind is considered, then the wave amplitude evolution, similar to the no-wind case, continues to be recurrent.
Translated by Vladimir A. Puchkin. 相似文献
998.
999.
J. A. Docobo V. S. Tamazian N. D. Melikian M. H. Eritsian A. A. Karapetian 《Astrophysics》2000,43(2):162-169
The results of photometric and polarimetric observations of the star Μ Cep at Byurakan Observatory are presented. Some interesting
correlations between the parameters of the star’s brightness variation and the degree of polarization of the light are obtained.
It is suggested that the recorded rapid changes in the degree of polarization may result from Μ Cep being a double star.
Translated from Astrofizika, Vol. 43, No. 2, pp. 219-228, April–June, 2000. 相似文献
1000.
A.M. Cherepashchuk 《Astrophysics and Space Science》2000,274(1-2):159-175
Various observational appearences of the effects of wind-wind collision for binary stellar systems have been discovered recently
in X-ray, UV, optical, IR and radio ranges. Recent 3D gas-dynamic simulations of the wind-wind collision regions in WR+O,
O+O and symbiotic binary systems allow to understand the physics of wind-wind collision effects, provide interpretation of
observational data and constrain basic parameters of winds as well as those of binary systems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献