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241.
Panning Mark P. Lognonné Philippe Bruce Banerdt W. Garcia Raphaël Golombek Matthew Kedar Sharon Knapmeyer-Endrun Brigitte Mocquet Antoine Teanby Nick A. Tromp Jeroen Weber Renee Beucler Eric Blanchette-Guertin Jean-Francois Bozdağ Ebru Drilleau Mélanie Gudkova Tamara Hempel Stefanie Khan Amir Lekić Vedran Murdoch Naomi Plesa Ana-Catalina Rivoldini Atillio Schmerr Nicholas Ruan Youyi Verhoeven Olivier Gao Chao Christensen Ulrich Clinton John Dehant Veronique Giardini Domenico Mimoun David Thomas Pike W. Smrekar Sue Wieczorek Mark Knapmeyer Martin Wookey James 《Space Science Reviews》2017,211(1-4):611-650
Space Science Reviews - The InSight lander will deliver geophysical instruments to Mars in 2018, including seismometers installed directly on the surface (Seismic Experiment for Interior Structure,... 相似文献
242.
John H. Heinbockel Tony C. Slaba Ram K. Tripathi Steve R. Blattnig John W. Norbury Francis F. Badavi Lawrence W. Townsend Thomas Handler Tony A. Gabriel Lawrence S. Pinsky Brandon Reddell Aric R. Aumann 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The HZETRN deterministic radiation code is one of several tools developed to analyze the effects of harmful galactic cosmic rays (GCR) and solar particle events on mission planning and shielding for astronauts and instrumentation. This paper is a comparison study involving the two Monte Carlo transport codes, HETC–HEDS and FLUKA and the deterministic transport code, HZETRN. Each code is used to transport an ion from the 1977 solar minimum GCR spectrum impinging upon a 20 g/cm2 aluminum slab followed by a 30 g/cm2 water slab. This research is part of a systematic effort of verification and validation to quantify the accuracy of HZETRN and determine areas where it can be improved. Comparisons of dose and dose equivalent values at various depths in the water slab are presented in this report. This is followed by a comparison of the proton and forward, backward and total neutron flux at various depths in the water slab. Comparisons of the secondary light ion 2H, 3H, 3He and 4He fluxes are also examined. 相似文献
243.
John M.A. Duncan Jadunandan Dash Peter M. Atkinson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Spatio-temporal dynamics in land surface phenology parameters observed over croplands can inform on crop-climate interactions and, elucidate local to regional scale vulnerabilities either due to climate change or prevailing sub-optimal agricultural practices. Here, we observe spatio-temporal trends in land surface phenology parameters (cropping intensity, length of growing season and productivity) for kharif and rabi cropping seasons from satellite data across the Indo-Gangetic Plains from 1982 to 2006. The productivity of the Indo-Gangetic Plains croplands is of regional importance and is a vital component of Indian national food security efforts. Aside from local and intra-state heterogeneity in observed trends there was a clear west-to-east gradient in cropping intensity. Key observed trends include increasing cropping intensity in the eastern IGP, increasing number of growing days per year in Bihar, Uttar Pradesh and Haryana and increasing productivity in both cropping seasons across the IGP. This information is a crucial input to integrated assessments of the croplands to ensure management of the agricultural system shifts towards a trajectory of climate-resilience and environmental sustainability. 相似文献
244.
Glenn JH 《Aerospace America》2003,41(2):12-14
Senator Glenn is interviewed about his experiences on Friendship 7 and the Shuttle Discovery, expectations of early astronauts, lunar missions, the International Space Station, international dimensions of space activities, public confidence in NASA, attracting young people to the aerospace industry, highlights of his career, and the future of flight. 相似文献
245.
Aymeric Spiga Don Banfield Nicholas A. Teanby François Forget Antoine Lucas Balthasar Kenda Jose Antonio Rodriguez Manfredi Rudolf Widmer-Schnidrig Naomi Murdoch Mark T. Lemmon Raphaël F. Garcia Léo Martire Özgür Karatekin Sébastien Le Maistre Bart Van Hove Véronique Dehant Philippe Lognonné Nils Mueller Ralph Lorenz David Mimoun Sébastien Rodriguez Éric Beucler Ingrid Daubar Matthew P. Golombek Tanguy Bertrand Yasuhiro Nishikawa Ehouarn Millour Lucie Rolland Quentin Brissaud Taichi Kawamura Antoine Mocquet Roland Martin John Clinton Éléonore Stutzmann Tilman Spohn Suzanne Smrekar William B. Banerdt 《Space Science Reviews》2018,214(7):109
In November 2018, for the first time a dedicated geophysical station, the InSight lander, will be deployed on the surface of Mars. Along with the two main geophysical packages, the Seismic Experiment for Interior Structure (SEIS) and the Heat-Flow and Physical Properties Package (HP3), the InSight lander holds a highly sensitive pressure sensor (PS) and the Temperature and Winds for InSight (TWINS) instrument, both of which (along with the InSight FluxGate (IFG) Magnetometer) form the Auxiliary Sensor Payload Suite (APSS). Associated with the RADiometer (RAD) instrument which will measure the surface brightness temperature, and the Instrument Deployment Camera (IDC) which will be used to quantify atmospheric opacity, this will make InSight capable to act as a meteorological station at the surface of Mars. While probing the internal structure of Mars is the primary scientific goal of the mission, atmospheric science remains a key science objective for InSight. InSight has the potential to provide a more continuous and higher-frequency record of pressure, air temperature and winds at the surface of Mars than previous in situ missions. In the paper, key results from multiscale meteorological modeling, from Global Climate Models to Large-Eddy Simulations, are described as a reference for future studies based on the InSight measurements during operations. We summarize the capabilities of InSight for atmospheric observations, from profiling during Entry, Descent and Landing to surface measurements (pressure, temperature, winds, angular momentum), and the plans for how InSight’s sensors will be used during operations, as well as possible synergies with orbital observations. In a dedicated section, we describe the seismic impact of atmospheric phenomena (from the point of view of both “noise” to be decorrelated from the seismic signal and “signal” to provide information on atmospheric processes). We discuss in this framework Planetary Boundary Layer turbulence, with a focus on convective vortices and dust devils, gravity waves (with idealized modeling), and large-scale circulations. Our paper also presents possible new, exploratory, studies with the InSight instrumentation: surface layer scaling and exploration of the Monin-Obukhov model, aeolian surface changes and saltation / lifing studies, and monitoring of secular pressure changes. The InSight mission will be instrumental in broadening the knowledge of the Martian atmosphere, with a unique set of measurements from the surface of Mars. 相似文献
246.
Christopher J. Mertens Michael F. Moyers Steven A. Walker John Tweed 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Recent developments in NASA’s deterministic High charge (Z) and Energy TRaNsport (HZETRN) code have included lateral broadening of primary ion beams due to small-angle multiple Coulomb scattering, and coupling of the ion-nuclear scattering interactions with energy loss and straggling. This new version of HZETRN is based on Green function methods, called GRNTRN, and is suitable for modeling transport with both space environment and laboratory boundary conditions. Multiple scattering processes are a necessary extension to GRNTRN in order to accurately model ion beam experiments, to simulate the physical and biological-effective radiation dose, and to develop new methods and strategies for light-ion radiation therapy. In this paper we compare GRNTRN simulations of proton lateral broadening distributions with beam measurements taken at Loma Linda University Proton Therapy Facility. The simulated and measured lateral broadening distributions are compared for a 250 MeV proton beam on aluminum, polyethylene, polystyrene, bone substitute, iron, and lead target materials. The GRNTRN results are also compared to simulations from the Monte Carlo MCNPX code for the same projectile-target combinations described above. 相似文献
247.
John Brophy 《Space Science Reviews》2011,163(1-4):251-261
Dawn??s ion propulsion system (IPS) is the most advanced propulsion system ever built for a deep-space mission. Aside from the Mars gravity assist it provides all of the post-launch ??V required for the mission including the heliocentric transfer to Vesta, orbit capture at Vesta, transfer to various Vesta science orbits, escape from Vesta, the heliocentric transfer to Ceres, orbit capture at Ceres, and transfer to the different Ceres science orbits. The ion propulsion system provides a total ??V of nearly 11 km/s, comparable to the ??V provided by the 3-stage launch vehicle, and a total impulse of 1.2×107 N?s. 相似文献
248.
All sampling representations of band-limited signals involve infinite sums. The truncation error associated with a given representation is defined as the difference between the signal and an approximating sum utilizing a finite number of terms. In this paper truncation error is expressed as a contour integral for Lagrange interpolation, general Hermite interpolation, the Shannon series (cardinal series), the Fogel derivative series, and multidimensional sampling expansions. Truncation error bounds are obtained under various constraints on the signal magnitude, spectral smoothness, and energy content. 相似文献
249.
Space Science Reviews - 相似文献
250.