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11.
The article presents an analysis of the Phobos-Grunt mission, a classification of its phases in terms of planetary protection, and the main principles of activities management and definition of actions for fulfilling the planetary-protection requirements developed by Committee on Space Research.  相似文献   
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New mineralogical, geochemical, and isotope data in combination with numerical modeling were used to reconstruct the physicochemical and geodynamic conditions of the formation of Pleistocene basalts of Kunashir Island. Although they are petrologically close to the Holocene basalts of Tyatya Volcano, their eruption occurred during a brief period of island arc extension, which was accompanied by the high degree melting of mantle wedge asthenosphere. Numerous geological, petrological, and paleogeographical data testify that Pleistocene is an important stage in the geodynamic reorganization of the Kuril island arc. This stage was responsible for uplifting of the southern islands above sea level accompanied by catastrophic endogenous events, deformation, topographic reorganization of the large area of the Sea of Japan and adjacent land, and final folding stage in the West Sakhalin Mountains.  相似文献   
14.
A. Yu. Martynov 《Petrology》2013,21(5):471-488
Geochemical data obtained on volcanic rocks produced during the early evolutionary stages in Kunashir Island provide insight into certain important aspect of the evolution of the subduction system. The mafic lavas of all age intervals exhibit clearly pronounced across-arc geochemical zoning, which implies that these rocks were produced in the environment of a subducted oceanic slab. The high Ba/Th and U/Th ratios of basalts from the frontal zones suggest that an important role in magma generation was played by a low-temperature aqueous fluid. The arc lavas of the Early Miocene, Pliocene, and Pliocene-Pleistocene episodes in the evolution of the island arc system provide evidence of the melting of subducted sediments, which testifies, when considered together with the calculated P-T conditions under which the high-Mg basalts were derived, that backarc tectono-magmatic processes affected subduction-related magmatic generation. Active mantle diapirism and volcanic activity in the opening Kurile Basin resulted in the heating of the suprasubduction mantle in the rear zone, the involvement of the upper sedimentary layer of the oceanic slab in the process of melting, and the eventual generation of basaltic magmas with unusual geochemical characteristics.  相似文献   
15.
On the base of CCD-observations made with the axial meridian circle of the Nikolaev Observatory from 2008 to 2009, we compiled a catalogue for astrometric positions and proper motions for 140321 stars located in an ecliptic zone and around high proper motion stars. The root-meansquare error for a star position is 20–65 mas in right ascension and 30–70 mas in declination. The UCAC2 catalogue is used as a reference for astrometric reductions. To derive stars’ proper motion and to estimate systematic errors of the compiled catalogue, cross-identification of the obtained data with modern astronomic catalogues Tycho2, 2MASS, CMC14, LSPM, PPMX, USNO-A2, and XPM-1.0 is performed. In addition to star position and proper motion, our catalogue contains photometric values B, V, r’, J, H, and K taken from other catalogues.  相似文献   
16.
European Venus Explorer (EVE): an in-situ mission to Venus   总被引:1,自引:0,他引:1  
The European Venus Explorer (EVE) mission was proposed to the European Space Agency in 2007, as an M-class mission under the Cosmic Vision Programme. Although it has not been chosen in the 2007 selection round for programmatic reasons, the EVE mission may serve as a useful reference point for future missions, so it is described here. It consists of one balloon platform floating at an altitude of 50–60 km, one descent probe provided by Russia, and an orbiter with a polar orbit which will relay data from the balloon and descent probe, and perform science observations. The balloon type preferred for scientific goals is one which oscillates in altitude through the cloud deck. To achieve this flight profile, the balloon envelope contains a phase change fluid, which results in a flight profile which oscillates in height. The nominal balloon lifetime is 7 days—enough for one full circumnavigation of the planet. The descent probe’s fall through the atmosphere takes 60 min, followed by 30 min of operation on the surface. The key measurement objectives of EVE are: (1) in situ measurement from the balloon of noble gas abundances and stable isotope ratios, to study the record of the evolution of Venus; (2) in situ balloon-borne measurement of cloud particle and gas composition, and their spatial variation, to understand the complex cloud-level chemistry; (3) in situ measurements of environmental parameters and winds (from tracking of the balloon) for one rotation around the planet, to understand atmospheric dynamics and radiative balance in this crucial region. The portfolio of key measurements is complemented by the Russian descent probe, which enables the investigation of the deep atmosphere and surface.  相似文献   
17.
A detailed mineralogical and geochemical study of basic volcanic rocks from the modern edifices of the Gorely (Q34-Q44) and Mutnovsky (Q32-Q4) volcanoes, as well as the results of numerical modeling with the COMAGMAT program, made it possible to estimate the role of fractional crystallization, the fluid regime, and geodynamic conditions in the petrogenesis of the studied basaltoids. The specific features of the evolution of magmas of the two volcanoes give grounds to suggest that beginning from the Late Pleistocene (Q34), all of the considered territory experienced a change in geodynamic regime, with an increasing role of extending strains in its evolution.  相似文献   
18.
The paper refers to the current status of asteroid hazard in Russia and abroad. The authors emphasize the relevance of a sober assessment of its real state and specific circumstances working from the principle of reasonable sufficiency. The paper presents a practical approach to the asteroid hazard problem. It consists of a proposal for a mission to the Apophis asteroid and to define the main parameters of this hazardous celestial body. The article also considers how the spacecraft would look, as well as its mission profile for the period of 2012–2014.  相似文献   
19.
A new phase of Venus research has started in Russia; the Federal Space Program includes the Venera-D design with the launch of the spacecraft scheduled for 2016. The mission comprises an orbiter, a descent vehicle, and balloon probes. The balloon probes will be placed at different altitudes in the cloud layer and under the clouds, where they are intended to last for a long time in the atmosphere of Venus. The successful implementation of the design will allow solving of quite a number of scientific tasks for comparative planetology.  相似文献   
20.
New data on the Hf, Pb, and Nd isotopes of the mafic rocks of various ages from Kunashir Island were used to address the nature of the sub-arc mantle of the southern segment of the Kuril island arc. At least since Late Cenozoic, its isotopic characteristics have been the MORB-type mantle of the Indian Ocean. Its boundary with the mantle reservoir of the Pacific MORB-type coincided probably with the Kuril-Kamchatka Trench.  相似文献   
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