排序方式： 共有29条查询结果，搜索用时 16 毫秒
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I. G. Mitrofanov A. S. Kozyrev D. I. Lisov A. A. Vostrukhin D. V. Golovin M. L. Litvak A. V. Malakhov M. I. Mokrousov S. Yu. Nikiforov A. B. Sanin 《Astronomy Letters》2016,42(4):251-259
This paper presents the water and chlorine content estimates on the bottom of the Martian crater Gale obtained by processing the data of active neutron sensing with the DAN experiment onboard theNASA “Curiosity”Mars rover at 412 spots along the 11-kilometer track. For 78% of the examined spots the water distribution in depth is found to be homogeneous with a mean content of 2.1±0.5% by mass (here and elsewhere variations correspond to the mean square deviations). For 22% of the examined spots the data require a two-layer model of water distribution down to the sensitivity limit of about 60 сm. The mean water content in upper layer of these spots is about 2?3% by mass, which is close to the content for spots with the homogeneous water distribution. In 8% of the examined spots the water content in the bottom layer at a depth of 27 ± 18 сm increases to 5.6 ± 2.7%. In 14% of the examined spots the water content in the bottom layer at a depth of 14 ± 7 сm decreases to 1.2 ± 0.5%. For interpretation of these results we conclude that the Gale crater has areas both with high and low water content, which correspond to distinct sedimentary layers from different past epochs, when sedimentation process took place underwater and in air correspondingly. 相似文献
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Mitrofanov I. G. Sanin A. B. Golovin D. V. Nikiforov S. Y. Litvak M. L. Bakhtin B. N. 《Solar System Research》2022,56(5):291-298
Solar System Research - Methods are discussed for studying the variability in space of the substance composition of the surface of Mars in experiments on gamma-ray spectroscopy on board a mobile... 相似文献
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V. I. Vybornov M. A. Livshits L. K. Kashapova I. G. Mitrofanov D. V. Golovin A. S. Kozyrev M. L. Litvak A. B. Sanin V. I. Tret’yakov W. Boynton K. Shinohara D. Hamara 《Astronomy Reports》2012,56(10):805-812
Observations of the hard X-ray and radio event of October 27, 2002 are analyzed. This flare was observed from near-Martian orbit by the HEND instrument developed at the Space Research Institute of the Russian Academy of Sciences and installed on the Mars Odyssey satellite. Although this powerful flare was observed far over the eastern solar limb, the extended source associated with the flare was detected by RHESSI at energies up to about 60 keV. The eruptive event was observed in the radio at the Nobeyama Radio Observatory. The properties of the X-ray radiation are used to calculate the spectrum of the accelerated electrons responsible for the observed radiation, assuming that the target is thick for a Martian observer and thin for a terrestrial observer. The results are compared with the results of radio observations. The conditions for electron propagation in the corona are discussed. 相似文献
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This paper explores the advantages of applying the concept of social-ecological resilience (SER) and the related thinking in transdisciplinary research. The theoretical reflections are exemplified by transdisciplinary research experiences using the concept of SER as a bridging concept in the field of climate-change adaptation instead of developing a new and very context-specific conceptual bridge. The findings are based on ontological reflections concerning the complex and hybrid phenomenon of climate change and the need for transdisciplinary research as well as on reflections on the performed interdisciplinary research and the exploratory transdisciplinary research approach with practitioners from the German administration. The experiences so far have shown that it was more focused on the general ideas of social-ecological resilience thinking instead of using the concept of SER as an analytical tool. We conclude that the use of a common conceptual framework in general and of social-ecological resilience thinking in particular offers tangible advantages in transdisciplinary research dealing with climate change and adaptation to the impacts of climate change. In our case, social-ecological resilience thinking helped—after translation into practical terms—to open the field for further consideration from the very beginning as well as to open the space for common creative work; to define the problem; and to choose the relevant variables to look at. 相似文献
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N. E. Demidov W. V. Boynton D. A. Gilichinsky M. T. Zuber A. S. Kozyrev M. L. Litvak I. G. Mitrofanov A. B. Sanin R. S. Saunders D. E. Smith V. I. Tretyakov D. Hamara 《Astronomy Letters》2008,34(10):713-723
We jointly analyze data from the High-Energy Neutron Detector (HEND) onboard the NASA Mars Odyssey spacecraft and data from the Mars Orbiter Laser Altimeter (MOLA) onboard the Mars Global Surveyor spacecraft. The former instrument measures the content of hydrogen (in the form of H2O or OH) in the subsurface layer of soil and the latter instrument measures the surface albedo with respect to the flux of solar energy. We have checked the presence of a correlation between these two data sets in various Martian latitude bands. A significant correlation has been found between these data at latitudes poleward of 40° in the northern hemisphere and at latitudes 40°–60° in the southern hemisphere. This correlation is interpreted as evidence for the presence of stable water ice in these regions under a dry layer of soil whose thickness is determined by the condition for equilibrium between the condensation of water from the atmosphere and its sublimation when heated by solar radiation. For these regions, we have derived an empirical relation between the flux of absorbed solar radiation and the thickness of the top dry layer. It allows the burial depth of the water ice table to be predicted with a sub-kilometer resolution based on near-infrared albedo measurements. We have found no correlation in the southern hemisphere at latitudes >60°, although neutron data also suggest that water ice is present in this region under a layer of dry soil. We conclude that the thickness of the dry layer in this region does not correspond to the equilibrium condition between the water ice table and the atmosphere. 相似文献
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M. A. Livshits I. V. Zimovets D. V. Golovin B. A. Nizamov V. I. Vybornov I. G. Mitrofanov A. S. Kozyrev M. L. Litvak A. B. Sanin V. I. Tretyakov 《Astronomy Reports》2017,61(9):791-804
The study of nonstationary processes in the Sun is of great interest, and multi-wavelength observations and the registration of magnetic fields have been carried out using both ground-based telescopes and several specialized spacecraft in near-Earth orbits in recent years. However, the acquisition of new, reliable information on their hard X-ray radiation remains necessary, in particular, if the corresponding spacecraft provide additional information, e.g., in regard to flare observations from directions other than the Sun–Earth direction. This paper presents a catalog of powerful solar flares registered by the High Energy Neutron Detector (HEND) designed at the Space Research Institute of the Russian Academy of Sciences. HEND is mounted onboard the 2001Mars Odyssey spacecraft. It operated successfully during the flight to Mars and is currently operating in near-Mars orbit. Apart from neutrons, HEND is sensitive to hard X-ray (up to 300 keV) and gamma-ray radiation (above 300 keV). This radiation is registered by two scintillators: an outer one that is sensitive to photons above 40 keV and an inner one sensitive to photons above 200 keV. The catalog was created using a new procedure for calibration of the data. For the most powerful 60 solar flares in the visible and far sides of the Sun (for a terrestrial observer), time profiles of the flare radiation summed over all channels of the X-ray, and in some cases the gamma-ray, bands are provided, as well as spectra and characteristics of power-law fits. The results of previous studies of the Sun using HEND and the potential for further use of these data are discussed. 相似文献
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S. M. Korotaev I. L. Trofimov S. V. Shabelyansky M. S. Zhdanov A. I. Lapitsky S. I. Sanin E. R. Martanus 《Physics of the Earth and Planetary Interiors》1990,60(1-4):115-119
Two geoelectric models of the transition zone between the continent and the Black Sea basin were constructed from a variety of independent exploratory methods using natural electromagnetic fields. The models presented characterize some important features of the deep structure of the sea-shore transition zone. In particular, geoelectric properties of the lithosphere beneath the Black Sea basin are found to be approximately oceanic. 相似文献
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Malakhov A. V. Mitrofanov I. G. Litvak M. L. Sanin A. B. Golovin D. V. Djachkova M. V. Nikiforov S. Yu. Anikin A. A. Lisov D. I. Lukyanov N. V. Mokrousov M. I. 《Astronomy Letters》2020,46(6):407-421
Astronomy Letters - We present the first results of Mars neutron sounding by FREND instrument onboard ESA’s Trace Gas Orbiter data analysis. Neutron flux mapping is performed with high... 相似文献