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261.
Selection of the Mars Science Laboratory Landing Site 总被引:1,自引:0,他引:1
M. Golombek J. Grant D. Kipp A. Vasavada R. Kirk R. Fergason P. Bellutta F. Calef K. Larsen Y. Katayama A. Huertas R. Beyer A. Chen T. Parker B. Pollard S. Lee Y. Sun R. Hoover H. Sladek J. Grotzinger R. Welch E. Noe?Dobrea J. Michalski M. Watkins 《Space Science Reviews》2012,170(1-4):641-737
The selection of Gale crater as the Mars Science Laboratory landing site took over five years, involved broad participation of the science community via five open workshops, and narrowed an initial >50 sites (25 by 20?km) to four finalists (Eberswalde, Gale, Holden and Mawrth) based on science and safety. Engineering constraints important to the selection included: (1)?latitude (±30°) for thermal management of the rover and instruments, (2)?elevation (<?1?km) for sufficient atmosphere to slow the spacecraft, (3)?relief of <100–130?m at baselines of 1–1000?m for control authority and sufficient fuel during powered descent, (4)?slopes of <30° at baselines of 2–5?m for rover stability at touchdown, (5)?moderate rock abundance to avoid impacting the belly pan during touchdown, and (6)?a?radar-reflective, load-bearing, and trafficable surface that is safe for landing and roving and not dominated by fine-grained dust. Science criteria important for the selection include the ability to assess past habitable environments, which include diversity, context, and biosignature (including organics) preservation. Sites were evaluated in detail using targeted data from instruments on all active orbiters, and especially Mars Reconnaissance Orbiter. All of the final four sites have layered sedimentary rocks with spectral evidence for phyllosilicates that clearly address the science objectives of the mission. Sophisticated entry, descent and landing simulations that include detailed information on all of the engineering constraints indicate all of the final four sites are safe for landing. Evaluation of the traversabilty of the landing sites and target “go to” areas outside of the ellipse using slope and material properties information indicates that all are trafficable and “go to” sites can be accessed within the lifetime of the mission. In the final selection, Gale crater was favored over Eberswalde based on its greater diversity and potential habitability. 相似文献
262.
K.C. Kim K. Abe H. Fuke T. Hams M.H. Lee Y. Makida S. Matsuda J.W. Mitchell J. Nishimura J.F. Ormes M. Sasaki E.S. Seo Y. Shikaze R.E. Streitmatter J. Suzuki K. Tanaka T. Yamagami A. Yamamoto T. Yoshida K. Yoshimura 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) was flown from Lynn Lake, Manitoba, Canada in August, 2000, during the maximum solar modulation period, with an average residual atmospheric overburden of 4.3 g/cm2. Precise spectral measurements of cosmic ray hydrogen isotopes from 0.178 GeV/n to 1.334 GeV/n were made during the 28.7 h of flight. This paper presents the measured energy spectra and their ratio, 2H/1H. The results are also compared with previous measurements and theoretical predictions. 相似文献
263.
C.K. Shum Hyongki Lee P.A.M. Abusali Alexander Braun Guy de Carufel Georgia Fotopoulos Attila Komjathy Chungyen Kuo 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Innovative processing of satellite radar altimetry over solid Earth has been successfully applied for observing geodynamic process of glacial isostatic adjustment over the former Laurentide Ice Sheet in the present-day Hudson Bay land region. In this contribution, a simulation is conducted to study the prospects of the applications of space-/airborne and land-based Global Navigation Satellite System (GNSS) reflectometry to synoptically observe global-scale geodynamic processes with a vertical accuracy of ∼2 mm/yr. 相似文献
264.
The Upgraded CARISMA Magnetometer Array in the THEMIS Era 总被引:1,自引:0,他引:1
I. R. Mann D. K. Milling I. J. Rae L. G. Ozeke A. Kale Z. C. Kale K. R. Murphy A. Parent M. Usanova D. M. Pahud E.-A. Lee V. Amalraj D. D. Wallis V. Angelopoulos K.-H. Glassmeier C. T. Russell H.-U. Auster H. J. Singer 《Space Science Reviews》2008,141(1-4):413-451
This review describes the infrastructure and capabilities of the expanded and upgraded Canadian Array for Realtime InvestigationS of Magnetic Activity (CARISMA) magnetometer array in the era of the THEMIS mission. Formerly operated as the Canadian Auroral Network for the OPEN Program Unified Study (CANOPUS) magnetometer array until 2003, CARISMA capabilities have been extended with the deployment of additional fluxgate magnetometer stations (to a total of 28), the upgrading of the fluxgate magnetometer cadence to a standard data product of 1 sample/s (raw sampled 8 samples/s data stream available on request), and the deployment of a new network of 8 pairs of induction coils (100 samples per second). CARISMA data, GPS-timed and backed up at remote field stations, is collected using Very Small Aperture Terminal (VSAT) satellite internet in real-time providing a real-time monitor for magnetic activity on a continent-wide scale. Operating under the magnetic footprint of the THEMIS probes, data from 5 CARISMA stations at 29–30 samples/s also forms part of the formal THEMIS ground-based observatory (GBO) data-stream. In addition to technical details, in this review we also outline some of the scientific capabilities of the CARISMA array for addressing all three of the scientific objectives of the THEMIS mission, namely: 1. Onset and evolution of the macroscale substorm instability, 2. Production of storm-time MeV electrons, and 3. Control of the solar wind-magnetosphere coupling by the bow shock, magnetosheath, and magnetopause. We further discuss some of the compelling questions related to these three THEMIS mission science objectives which can be addressed with CARISMA. 相似文献
265.
Kyeong Ja Kim Joo-Hee Lee Haingja Seo Gwanghyeok Ju Sang-Ryool Lee Gi-Hyuk Choi Eun-Sup Sim Tai Sik Lee 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Korea is planning a series of lunar space programs in 2020 starting with a lunar orbiter and a lander with a rover. Compared to other countries, Korea has a relatively brief history in space and planetary sciences. With the expected Korean missions on the near-term horizon and the relatively few Korean planetary scientists, Korea Institute of Geoscience and Mineral Resources (KIGAM) has established a new planetary research group focusing on development of prospective lunar instruments, analysis of the publicly available planetary data of the Moon, organizing nationwide planetary workshops, and initiating planetary educational programs with academic institutions. Korea has also initiated its own rocket development program, which could acquire a rocket-launch capability toward the Korean lunar mission. For the prospective Korea’s lunar science program, feasibility studies for some candidate science payloads have been started since 2010 for an orbiter and a lander. The concept design of each candidate instrument has been accomplished in 2012. It is expected that the development of science payloads may start by 2014 as Phase A. Not only developing hardware required for the lunar mission but also educational activities for young students are high priorities for Korea. The new plan of the Korean lunar mission can be successfully accomplished with international cooperative outreach programs in conjunction with internationally accessible planetary data system (PDS). This paper introduces the KIGAM’s international cooperative planetary research and educational programs and also summarizes other nationwide new developments for Korean lunar research projects at Kyung Hee University and Hanyang University. 相似文献
266.
提出根据载客量、航程、巡航速度和高度即可初步确定斜置飞翼超声速旅客机气动外形参数的方法.讨论了对称面弦长的选取范围,确定了展弦比、起飞翼载荷与展长的关系,提出了展弦比、起飞翼载荷的选取原则,并推导了油箱展向长度和客舱展向长度迭代公式.为了研究技术要求对斜置飞翼超声速旅客机气动外形参数的影响,对载客量250~550、航程6500~10000 km、升阻比11~12内若干设计点进行了研究分析.结果表明,所设计的飞翼存在一起飞重量阈值,当起飞重量小于该阈值时机翼面积由展弦比下限确定,当起飞重量大于此阈值时机翼面积由起飞翼载荷上限确定;提高巡航升阻比可减小由起飞翼载荷上限确定的机翼面积. 相似文献
267.
M. Scholer G. Mann S. Chalov M.I. Desai L.A. Fisk J.R. Jokipii R. Kallenbach E. Keppler J. Kóta H. Kunow M.A. Lee T.R. Sanderson G.M. Simnett 《Space Science Reviews》1999,89(1-2):369-399
On the basis of the observational picture established in the report of Mason, von Steiger et al. (1999) the status of theoretical models on origin, injection, and acceleration of particles associated with Corotating Interaction
Regions (CIRs) is reviewed. This includes diffusive or first-order Fermi acceleration at oblique shocks, adiabatic deceleration
in the solar wind, stochastic acceleration in Alfvén waves and oblique propagating magnetosonic waves, and shock surfing as
possible injection mechanism to discriminate pickup ions from solar wind ions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
268.
C. Carr E. Cupido C. G. Y. Lee A. Balogh T. Beek J. L. Burch C. N. Dunford A. I. Eriksson R. Gill K. H. Glassmeier R. Goldstein D. Lagoutte R. Lundin K. Lundin B. Lybekk J. L. Michau G. Musmann H. Nilsson C. Pollock I. Richter J. G. Trotignon 《Space Science Reviews》2007,128(1-4):629-647
The Rosetta Plasma Consortium (RPC) will make in-situ measurements of the plasma environment of comet 67P/Churyumov-Gerasimenko.
The consortium will provide the complementary data sets necessary for an understanding of the plasma processes in the inner
coma, and the structure and evolution of the coma with the increasing cometary activity. Five sensors have been selected to
achieve this: the Ion and Electron Sensor (IES), the Ion Composition Analyser (ICA), the Langmuir Probe (LAP), the Mutual
Impedance Probe (MIP) and the Magnetometer (MAG). The sensors interface to the spacecraft through the Plasma Interface Unit
(PIU). The consortium approach allows for scientific, technical and operational coordination, and makes optimum use of the
available mass and power resources. 相似文献
269.
Scott D. Barthelmy Louis M. Barbier Jay R. Cummings Ed E. Fenimore Neil Gehrels Derek Hullinger Hans A. Krimm Craig B. Markwardt David M. Palmer Ann Parsons Goro Sato Masaya Suzuki Tadayuki Takahashi Makota Tashiro Jack Tueller 《Space Science Reviews》2005,120(3-4):143-164
he burst alert telescope (BAT) is one of three instruments on the
Swift MIDEX spacecraft to study gamma-ray bursts (GRBs). The BAT first detects the GRB and localizes the burst direction to an
accuracy of 1–4 arcmin within 20 s after the start of the event. The GRB trigger initiates an autonomous spacecraft slew to
point the two narrow field-of-view (FOV) instruments at the burst location within 20–70 s so to make follow-up X-ray and optical
observations. The BAT is a wide-FOV, coded-aperture instrument with a CdZnTe detector plane. The detector plane is composed
of 32,768 pieces of CdZnTe (4×4×2 mm), and the coded-aperture mask is composed of ∼52,000 pieces of lead (5×5×1 mm) with a
1-m separation between mask and detector plane. The BAT operates over the 15–150 keV energy range with ∼7 keV resolution,
a sensitivity of ∼10−8 erg s−1 cm−2, and a 1.4 sr (half-coded) FOV. We expect to detect > 100 GRBs/year for a 2-year mission. The BAT also performs an all-sky
hard X-ray survey with a sensitivity of ∼2 m Crab (systematic limit) and it serves as a hard X-ray transient monitor. 相似文献
270.