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111.
J. Biele S. Ulamec M. Hilchenbach N.I. Kömle 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
A key aspect for understanding the astrobiological potential of planets and moons in the Solar system is the analysis of material embedded in or underneath icy layers on the surface. In particular in case of the icy crust of Jupiters moon Europa such investigation would be of greatest interest. For a Europa lander to be launched in the 2020–2030 timeframe, we propose to use a simplified instrumented melting probe which is able to access and sample depths of a few meters without the necessity of heavy and complicated drilling equipment. 相似文献
112.
Development of thermal sensors and drilling systems for lunar and planetary regoliths 总被引:1,自引:0,他引:1
N.I. Kömle E. Kaufmann G. Kargl Yang Gao Xu Rui 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We consider some novel concepts for thermal properties experiments aboard lunar landers or rovers, that may lead to an improved understanding of both the structure of the lunar near surface layers and the lunar thermal history. The new instruments could be developed using the experience and heritage from recently developed systems, like the Rosetta Lander thermal conductivity experiment MUPUS and existing designs used for terrestrial measurements of thermal conductivity. We describe shortly the working principle of such sensors and the main challenges faced when using them in the airless regolith layers of the Moon or other airless bodies. In addition new concepts to create appropriate drill holes for thermal and other measurements in the lunar regolith are discussed. 相似文献
113.
M. Amenomori S. Ayabe X.J. Bi D. Chen S.W. Cui Danzengluobu L.K. Ding X.H. Ding C.F. Feng Zhaoyang Feng Z.Y. Feng X.Y. Gao Q.X. Geng H.W. Guo H.H. He M. He K. Hibino N. Hotta Haibing Hu H.B. Hu J. Huang Q. Huang H.Y. Jia F. Kajino K. Kasahara Y. Katayose C. Kato K. Kawata Labaciren G.M. Le A.F. Li J.Y. Li Y.-Q. Lou H. Lu S.L. Lu X.R. Meng K. Mizutani J. Mu K. Munakata A. Nagai H. Nanjo M. Nishizawa M. Ohnishi I. Ohta H. Onuma T. Ouchi S. Ozawa J.R. Ren T. Saito T.Y. Saito 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
114.
E.L. Afraimovich N.P. Perevalova I.V. Zhivetiev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We developed a method of estimation of a relative amplitude dI/I of the total electron content (TEC) variations in the ionosphere as deduced from the data of the global GPS receivers network. To obtain statistically significant results we picked out three latitudinal belts provided in the Internet by the maximum number of GPS sites. They are high-latitudinal belt (50–80°N, 200–300°E; 59 sites), mid latitude belt (20–50°N, 200–300°E; 817 sites), and equatorial belt (±20°N, 0–360°E; 76 sites). The results of the analysis of the diurnal and latitudinal dependencies of dI/I and dI/I distribution probability for 52 days with different levels of geomagnetic activity are presented. It was found that on average the relative amplitude of the TEC variations varies within the range 0–10% proportionally to the value of the Kp geomagnetic index. In quiet conditions the relative amplitude dI/I of the TEC variations at night significantly exceeds the daytime relative amplitude. At high levels of magnetic field disturbances, the geomagnetic control of the amplitude of TEC variations at high and middle latitudes is much more significant than the regular diurnal variations. At the equatorial belt, on average, the amplitude of TEC variations in quiet and disturbed periods almost does not differ. The obtained results may be useful for development of the theory of ionospheric irregularities. 相似文献
115.
J.-A. Sauvaud D. Larson C. Aoustin D. Curtis J.-L. Médale A. Fedorov J. Rouzaud J. Luhmann T. Moreau P. Schröder P. Louarn I. Dandouras E. Penou 《Space Science Reviews》2008,136(1-4):227-239
SWEA, the solar wind electron analyzers that are part of the IMPACT in situ investigation for the STEREO mission, are described. They are identical on each of the two spacecraft. Both are designed to provide detailed measurements of interplanetary electron distribution functions in the energy range 1~3000 eV and in a 120°×360° solid angle sector. This energy range covers the core or thermal solar wind plasma electrons, and the suprathermal halo electrons including the field-aligned heat flux or strahl used to diagnose the interplanetary magnetic field topology. The potential of each analyzer will be varied in order to maintain their energy resolution for spacecraft potentials comparable to the solar wind thermal electron energies. Calibrations have been performed that show the performance of the devices are in good agreement with calculations and will allow precise diagnostics of all of the interplanetary electron populations at the two STEREO spacecraft locations. 相似文献
116.
I. C. F. Mueller-Wodarg D. F. Strobel J. I. Moses J. H. Waite J. Crovisier R. V. Yelle S. W. Bougher R. G. Roble 《Space Science Reviews》2008,139(1-4):191-234
This paper summarizes the understanding of aeronomy of neutral atmospheres in the solar system, discussing most planets as well as Saturn’s moon Titan and comets. The thermal structure and energy balance is compared, highlighting the principal reasons for discrepancies amongst the atmospheres, a combination of atmospheric composition, heliocentric distance and other external energy sources not common to all. The composition of atmospheres is discussed in terms of vertical structure, chemistry and evolution. The final section compares dynamics in the upper atmospheres of most planets and highlights the importance of vertical dynamical coupling as well as magnetospheric forcing in auroral regions, where present. It is shown that a first order understanding of neutral atmospheres has emerged over the past decades, thanks to the combined effects of spacecraft and Earth-based observations as well as advances in theoretical modeling capabilities. Key gaps in our understanding are highlighted which ultimately call for a more comprehensive programme of observation and laboratory measurements. 相似文献
117.
S.I. Oronsaye L.A. McKinnell J.B. Habarulema 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
A new version of global empirical model for the ionospheric propagation factor, M(3000)F2 prediction is presented. Artificial neural network (ANN) technique was employed by considering the relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. This new version is an update to the previous neural network based M(3000)F2 global model developed by Oyeyemi et al. (2007), and aims to address the inadequacy of the International Reference Ionosphere (IRI) M(3000)F2 model (the International Radio Consultative Committee (CCIR) M(3000)F2 model). The M(3000)F2 has been found to be relatively inaccurate in representing the diurnal structure of the low latitude region and the equatorial ionosphere. In particular, the existing hmF2 IRI model is unable to reproduce the sharp post-sunset drop in M(3000)F2 values, which correspond to a sharp post-sunset peak in the peak height of the F2 layer, hmF2. Data from 80 ionospheric stations globally, including a good number of stations in the low latitude region were considered for this work. M(3000)F2 hourly values from 1987 to 2008, spanning all periods of low and high solar activity were used for model development and verification process. The ability of the new model to predict the M(3000)F2 parameter especially in the low latitude and equatorial regions, which is known to be problematic for the existing IRI model is demonstrated. 相似文献
118.
E.S. Seo T. Anderson D. Angelaszek S.J. Baek J. Baylon M. Buénerd M. Copley S. Coutu L. Derome B. Fields M. Gupta J.H. Han I.J. Howley H.G. Huh Y.S. Hwang H.J. Hyun I.S. Jeong D.H. Kah K.H. Kang D.Y. Kim H.J. Kim K.C. Kim M.H. Kim K. Kwashnak J. Lee M.H. Lee J.T. Link L. Lutz A. Malinin A. Menchaca-Rocha J.W. Mitchell S. Nutter O. Ofoha H. Park I.H. Park J.M. Park P. Patterson J.R. Smith J. Wu Y.S. Yoon 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The Cosmic Ray Energetics And Mass (CREAM) instrument is configured with a suite of particle detectors to measure TeV cosmic-ray elemental spectra from protons to iron nuclei over a wide energy range. The goal is to extend direct measurements of cosmic-ray composition to the highest energies practical, and thereby have enough overlap with ground based indirect measurements to answer questions on cosmic-ray origin, acceleration and propagation. The balloon-borne CREAM was flown successfully for about 161 days in six flights over Antarctica to measure elemental spectra of Z = 1–26 nuclei over the energy range 1010 to >1014 eV. Transforming the balloon instrument into ISS-CREAM involves identification and replacement of components that would be at risk in the International Space Station (ISS) environment, in addition to assessing safety and mission assurance concerns. The transformation process includes rigorous testing of components to reduce risks and increase survivability on the launch vehicle and operations on the ISS without negatively impacting the heritage of the successful CREAM design. The project status, including results from the ongoing analysis of existing data and, particularly, plans to increase the exposure factor by another order of magnitude utilizing the International Space Station are presented. 相似文献
119.
Analysis of the ionosphere/plasmasphere electron content variability during strong geomagnetic storm
Iu.V. Cherniak I.E. Zakharenkova D. Dzubanov A. Krankowski 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The ionosphere/plasmasphere electron content (PEC) variations during strong geomagnetic storms in November 2004 were estimated by combining of mid-latitude Kharkov incoherent scatter radar observations and GPS TEC data derived from global TEC maps. The comparison between two independent measurements was performed by analysis of the height-temporal distribution for specific location corresponding to the mid-latitudes of Europe. The percentage contribution of PEC to GPS TEC indicated the clear dependence from the time with maximal values (more than 70%) during night-time. During day-time the lesser values (30–45%) were observed for quiet geomagnetic conditions and rather high values of the PEC contribution to GPS TEC (up to 90%) were observed during strong negative storm. These changes can be explained by the competing effects of electric fields and winds, which tend to raise the layer to the region with lower loss rate and movement of the ionospheric plasma to the plasmasphere. 相似文献
120.
本文描述的是研究爆炸成型发射弹(EFP)模型的流场及超高速空气动力特性所用的弹道试验设备;简要报导了记录全尺寸干涉图形的技术;对径向密度分布再现的方法进行了讨论;在零攻角实验时不同模型的空气动力阻力是采用简化方法来计算的;对各种不同EFP型式的气动稳定性提出了定性估计的方法;并阐述了用于组合体超高速飞行特性研究的数值计算技术的基本原理 相似文献