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221.
火星太阳电池翼除尘方法综述   总被引:5,自引:0,他引:5  
“萤火一号”火星探测器即将发射升空,标志着我国火星探测计划实施的开始。然而,火星尘埃在范德华力和静电力的作用下积聚在太阳电池翼的表面,使其转换效率下降,影响火星探测器的寿命。因此,开展火星太阳电池翼除尘技术的研究是非常有意义的。文章主要介绍了火星太阳电池翼的除尘方法,特别是目前最受关注的电帘除尘方法,并对其基本结构、除尘原理、除尘效率和透光性做了详细的描述,对开展火星太阳电池翼除尘技术的研究具有一定的参考作用。  相似文献   
222.
萤火一号火星轨道器开环追踪技术   总被引:2,自引:0,他引:2  
中国首个火星探测器萤火一号计划于2009年10月和俄罗斯的火卫一采样探测器一道发射升空。萤火一号将探测火星的空间环境,并验证深空导航测控与通信技术。与常规的火星探测任务不同,该探测器的轨道与位置测量主要利用天文甚长基线干涉测量技术、开环跟踪测量技术、差分单程测距测速技术、同波束干涉测量技术以及单程Doppler测速技术承担。  相似文献   
223.
Supposing future orbiting and landing collaborative exploration mission as the potential project background, this paper addresses the issue of Mars entry integrated navigation using radio beacon, flush air data sensing system (FADS), and inertial measurement unit (IMU). The range and Doppler information sensed from an orbiting radio beacon, the dynamic pressure and heating data sensed from flush air data sensing system, and acceleration and attitude angular rate outputs from an inertial measurement unit are integrated in an unscented Kalman filter to perform state estimation and suppress the system and measurement noise. Computer simulations show that the proposed integrated navigation scheme can enhance the navigation accuracy, which enables precise entry guidance for the given Mars orbiting and landing collaborative exploration mission.  相似文献   
224.
Habitat in lava tubes recently discovered on the Moon and Mars, should become a unifying concept for occupancy. Basic motivations and specifications for such a habitat are briefly reviewed.  相似文献   
225.
在简述火星与地球大气飞行环境差异的基础上,分析研究了火星飞机主要布局特征和动力推进问题;阐述了国外开展火星飞机研究发展的地面模拟设备--火星风洞的情况,意在跟踪国外新技术走向,为国内航空航天未来发展提供参考.  相似文献   
226.
The High Resolution Stereo Camera (HRSC) onboard the Mars Express spacecraft in orbit about Mars has four detector channels dedicated to produce images in four spectral channels. Utilizing these spectrophotometric data requires understanding the instrument radiometric calibration and other photometric properties of the data. We present here some results of our investigation into the HRSC color data characteristics. This covers comparison of HRSC measurements with those of telescopes and the Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité (OMEGA) instrument, also on Mars Express. We also investigate the dependence of HRSC Color measurements on solar phase angle and altitude of the Mars surface. These results confirm and extend our earlier findings [McCord, T.B., Adams, J.B., Bellucci, G., Combe, J.-Ph., Hansen, G., Hoffman, H., Jaumann, R., Lumme, K., Neukum, G., Pinet, P., Poulet, F., the HRSC Co-I Team, The Mars Express high Resolution Stereo Camera spectrophotometric data: characteristics and science analysis. J. Geophys. Res. 112, E6, 2007.]. A basic finding from our study is that there are nearly constant offsets between the I/F value derived from the HRSC data and those determined from OMEGA and groundbased telescope measurements, especially in the HRSC red bandpass. These offsets are nearly independent of solar phase angle and Mars surface altitude but are considerably larger for the one comparison at Phobos we were able to make. Several hypotheses could explain these effects: atmospheric scattering, surface photometric effects, shift of the spatial registration or calibration. All these possibilities were investigated.  相似文献   
227.
NASA Planetary Protection Policy requires that Category IV missions such as those going to the surface of Mars include detailed assessment and documentation of the bioburden on the spacecraft at launch. In the prior missions to Mars, the approaches used to estimate the bioburden could easily be conservative without penalizing the project because spacecraft elements such as the descent and landing stages had relatively small surface areas and volumes. With the advent of a large spacecraft such as Mars Science Laboratory (MSL), it became necessary for a modified—still conservative but more pragmatic—statistical treatment be used to obtain the standard deviations and the bioburden densities at about the 99.9% confidence limits. This article describes both the Gaussian and Poisson statistics that were implemented to analyze the bioburden data from the MSL spacecraft prior to launch. The standard deviations were weighted by the areas sampled with each swab or wipe. Some typical cases are given and discussed.  相似文献   
228.
贾贺  荣伟 《航天器工程》2013,22(4):109-115
对欧洲航天局(ESA)火星探测的ExoMars 2016计划进行了概述,着重分析了进入、减速、着陆验证任务的关键环节,详细分析了进入、减速、着陆验证的任务组成、任务目标、任务规划以及相关关键技术等。结合我国火星探测目前的技术状态,需要针对进入、减速、着陆各关键技术进行合理的规划,并适时开展相关的试验验证。首先完成整个火星探测进入、减速、着陆平台的验证与研制,再进一步开展深入的火星探测科学任务研究。文章所述内容和分析可为我国下一步开展火星等深空探测任务提供参考。  相似文献   
229.
We have studied the loss of O+ and O+ 2 ions at Mars with a numerical model. In our quasi-neutral hybrid model ions (H+, He++, O+, O+ 2) are treated as particles while electrons form a massless charge-neutralising fluid. The employed model version does not include the Martian magnetic field resulting from the crustal magnetic anomalies. In this study we focus the Martian nightside where the ASPERA instrument on the Phobos-2 spacecraft and recently the ASPERA-3 instruments on the Mars Express spacecraft have measured the proprieties of escaping atomic and molecular ions, in particular O+ and O+ 2 ions. We study the ion velocity distribution and how the escaping planetary ions are distributed in the tail. We also create similar types of energy-spectrograms from the simulation as were obtained from ASPERA-3 ion measurements. We found that the properties of the simulated escaping planetary ions have many qualitative and quantitative similarities with the observations made by ASPERA instruments. The general agreement with the observations suggest that acceleration of the planetary ions by the convective electric field associated with the flowing plasma is the key acceleration mechanism for the escaping ions observed at Mars.  相似文献   
230.
介绍了低成本、高稳定的固态电压标准器的研制 ,该标准器可取代 0 .0 0 0 5级以下的标准电池 ,具有较高的应用和推广价值。  相似文献   
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