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1.
Chandrayaan-1: Science goals 总被引：1，自引：0，他引：1
N. Bhandari 《Journal of Earth System Science》2005,114(6):701-709
The primary objectives of the Chandrayaan-1 mission are simultaneous chemical, mineralogical and topographic mapping of the
lunar surface at high spatial resolution. These data should enable us to understand compositional variation of major elements,
which in turn, should lead to a better understanding of the stratigraphic relationships between various litho units occurring
on the lunar surface. The major element distribution will be determined using an X-ray fluorescence spectrometer (LEX), sensitive
in the energy range of 1–10 keV where Mg, Al, Si, Ca and Fe give their Kα lines. A solar X-ray monitor (SXM) to measure the
energy spectrum of solar X-rays, which are responsible for the fluorescent X-rays, is included. Radioactive elements like
Th will be measured by its 238.6 keV line using a low energy gamma-ray spectrometer (HEX) operating in the 20–250 keV region.
The mineral composition will be determined by a hyper-spectral imaging spectrometer (HySI) sensitive in the 400–920 nm range.
The wavelength range is further extended to 2600 nm where some spectral features of the abundant lunar minerals and water
occur, by using a near-infrared spectrometer (SIR-2), similar to that used on the Smart-1 mission, in collaboration with ESA.
A terrain mapping camera (TMC) in the panchromatic band will provide a three-dimensional map of the lunar surface with a spatial
resolution of about 5 m. Aided by a laser altimeter (LLRI) to determine the altitude of the lunar craft, to correct for spatial
coverage by various instruments, TMC should enable us to prepare an elevation map with an accuracy of about 10 m.
Four additional instruments under international collaboration are being considered. These are: a Miniature Imaging Radar Instrument
(mini-SAR), Sub Atomic Reflecting Analyser (SARA), the Moon Mineral Mapper (M3) and a Radiation Monitor (RADOM). Apart from
these scientific payloads, certain technology experiments have been proposed, which may include an impactor which will be
released to land on the Moon during the mission.
Salient features of the mission are described here. The ensemble of instruments onboard Chandrayaan-1 should enable us to
accomplish the science goals defined for this mission. 相似文献
2.
Ananth Krishna N. S. Gopinath N. S. Hegde N. K. Malik 《Journal of Earth System Science》2005,114(6):739-748
The Chandrayaan-1 mission proposes to put a 550 kg lunarcraft into Geostationary Transfer Orbit (GTO) using the Polar Satellite
Launch Vehicle (PSLV) which will subsequently be transferred into a 100 km circular lunar polar orbit for imaging purposes.
In this paper, we describe certain aspects of mission strategies which will allow optimum power generation and imaging of
the lunar surface.
The lunar orbit considered is circular and polar and therefore nearly perpendicular to the ecliptic plane. Unlike an Earth
orbiting remote sensing satellite, the orbit plane of lunar orbiter is inertially fixed as a consequence of the very small
oblateness of the Moon. The Earth rotates around the Sun once a year, resulting in an apparent motion of Sun around this orbit
in a year. Two extreme situations can be identified concerning the solar illumination of the lunar orbit, noon/midnight orbit,
where the Sun vector is parallel to the spacecraft orbit plane and dawn/dusk orbit, where the Sun vector is perpendicular
to the spacecraft orbit plane. This scenario directly affects the solar panel configuration. In case the solar panels are
not canted, during the noon/midnight orbit, 100% power is generated, whereas during the dawn/dusk orbit, zero power is generated.
Hence for optimum power generation, canting of the panels is essential. Detailed analysis was carried out to fix optimum canting
and also determine a strategy to maintain optimum power generation throughout the year. The analysis led to the strategy of
180‡ yaw rotation at noon/midnight orbits and flipping the solar panel by 180‡ at dawn/dusk orbits. This also resulted in
the negative pitch face of the lunarcraft to be an anti-sun panel, which is very useful for thermal design, and further to
meet cooling requirements of the spectrometers.
In principle the Moon’s surface can be imaged in 28 days, because the orbit chosen and the payload swath provide adequate
overlap. However, in reality it is not possible to complete the imaging in 28 days due to various mission constraints like
maximum duration of imaging allowed keeping in view the SSR sizing and payloads data input rate, time required for downlinking
the payload data, data compression requirements and visibility of the lunarcraft for the Bangalore DSN. In each cycle, all
the latitudes are swept. Due to the constraints mentioned, only 60‡ latitude arc coverage is possible in each orbit. As Bangalore
DSN is the only station, half of the orbits in a day are not available. The longitudinal gaps because of non-visibility are
covered in the next cycle by Bangalore DSN. Hence, in the firstprime imaging season, only 25% of the prime imaging zones are covered, and an additional threeprime imaging seasons are required for a full coverage of the Moon in two years. Strategy is also planned to cover X-ray payload coverage considering
swath and orbit shift. 相似文献
3.
月球尘埃研究具有重要的科学和工程价值。目前对月球尘埃运动规律、运动机理等的了解非常有限,对尘埃运动物理参数缺少系统的定量测量,严重制约了月球尘埃的科学研究。阿波罗17号宇航员观察到的月尘扬起及其物理机制迄今为止在科学上仍然是一个谜。中国的嫦娥三号月球探测任务得到了月面上的尘埃沉积数据及尘埃活动高度数据,表明尘埃活动具有显著的地域差异。在嫦娥五号采样返回任务中将研究月尘带电方面的物理特性。探月后续任务中如果能够在高纬度地区首次系统地定量测量月尘运动的物理参数,将会揭示不同经纬度区域、不同太阳光照条件、不同太阳风条件、不同地形条件下的尘埃活动规律及其关键影响因素,对高精度数值模型的建立及其参数选择提供定量限制,必将取得新的重要科学发现。 相似文献
4.
J. N. Goswami D. Banerjee N. Bhandari M. Shanmugam Y. B. Acharya D. V. Subhedar M. R. Sharma C. N. Umapathy P. Sreekumar M. Sudhakar L. Abraham P. C. Agrawal 《Journal of Earth System Science》2005,114(6):733-738
The Chandrayaan-1 mission to the Moon scheduled for launch in late 2007 will include a high energy X-ray spectrometer (HEX)
for detection of naturally occurring emissions from the lunar surface due to radioactive decay of the238U and232Th series nuclides in the energy region 20–250 keV. The primary science objective is to study the transport of volatiles on
the lunar surface by detection of the 46.5 keV line from radioactive210Pb, a decay product of the gaseous222Rn, both of which are members of the238U decay series. Mapping of U and Th concentration over the lunar surface, particularly in the polar and U-Th rich regions
will also be attempted through detection of prominent lines from the U and Th decay series in the above energy range. The
low signal strengths of these emissions require a detector with high sensitivity and good energy resolution. Pixelated Cadmium-Zinc-Telluride
(CZT) array detectors having these characteristics will be used in this experiment. Here we describe the science considerations
that led to this experiment, anticipated flux and background (lunar continuum), the choice of detectors, the proposed payload
configuration and plans for its realization 相似文献
5.
中国嫦娥工程三期将进行月球样品的采集与返回,这是继美国Apollo和前苏联Luna之后,国际上最新的月球样品返回计划。月球样品的存储与管理方法将成为中国探月工程中亟待解决的重要问题之一。特别是如何最大程度地保持月球样品的科学研究价值,避免或减少可能的样品污染等问题,不仅为工程部门所关心,也是月球科学家所极为关注的问题。文中主要回顾和总结了美国Apollo月球样品的处理与保存方法,包括月球样品实验室简况、月球样品初步处理方法、月球样品初步测试分析及相关实验简介和月球样品的保存方法等内容,以期为中国月球样品的返回和地面存储提供有益的借鉴。 相似文献
6.
The elemental abundances of lunar surface are the important clues to study the formation and evolution history of the Moon. In 2010, China＇s Chang＇E-2 （CE-2） lunar orbiter carried a set of X-ray spectrometer （XRS） to investigate the elemental abundances of the lunar surface. During CE-2＇s life span around the Moon, the XRS ex- perienced several events of solar flare. The X-ray solar monitor onboard recorded the spectra of solar X-rays at the same time. In this paper, we introduced the XRS instrument and data product. We analyzed the characteristics of the XRS data. Using the data obtained during an M solar flare event which had occurred on Feb. 16, 201 l, we derived the elemental abundances ofMg, A1, Si, Ca and Fe of the lunar surface in the Oceanus Procellarum. Finally, we dis- cussed the factors that influence the accuracy of the inversion. 相似文献
7.
Solar wind (SW) helium, neon, and argon trapped in a bulk metallic glass (BMG) target flown on NASA’s Genesis mission were analyzed for their bulk composition and depth-dependent distribution. The bulk isotopic and elemental composition for all three elements is in good agreement with the mean values observed in the Apollo Solar Wind Composition (SWC) experiment. Conversely, the He fluence derived from the BMG is up to 30% lower than values reported from other Genesis bulk targets or in-situ measurements during the exposure period. SRIM implantation simulations using a uniform isotopic composition and the observed bulk velocity histogram during exposure reproduces the Ne and Ar isotopic variations with depth within the BMG in a way which is generally consistent with observations. The similarity of the BMG release patterns with the depth-dependent distributions of trapped solar He, Ne, and Ar found in lunar and asteroidal regolith samples shows that also the solar noble gas record of extraterrestrial samples can be explained by mass separation of implanted SW ions with depth. Consequently, we conclude that a second solar noble gas component in lunar samples, referred to as the “SEP” component, is not needed. On the other hand, a small fraction of the total solar gas in the BMG released from shallow depths is markedly enriched in the light isotopes relative to predictions from implantation simulations with a uniform isotopic composition. Contributions from a neutral solar or interstellar component are too small to explain this shallow sited gas. We tentatively attribute this superficially implanted gas to low-speed, current-sheet related SW, which was fractionated in the corona due to inefficient Coulomb drag. This fractionation process could also explain relatively high Ne/Ar elemental ratios in the same initial gas fraction. 相似文献
8.
H. Mizutani A. Fujimura S. Tanaka H. Shiraishi T. Nakjima 《Journal of Earth System Science》2005,114(6):763-768
The scientific objective of the Lunar-A, Japanese Penetrator Mission, is to explore the lunar interior by seismic and heat-flow
experiments. Two penetrators containing two seismometers (horizontal and vertical components) and heat-flow probes will be
deployed from a spacecraft onto the lunar surface, one on the near-side and the other on the far-side of the moon. The data
obtained by the penetrators will be transmitted to the earth station via the Lunar-A mother spacecraft orbiting at an altitude
of about 200 km.
The spacecraft of a cylindrical shape, 2.2 m in maximum diameter and 1.7 m in height, is designed to be spin-stabilized. The
spacecraft will be inserted into an elliptic lunar orbit, after about a half-year cruise during which complex manoeuvering
is made using the lunar-solar gravity assist. After lunar orbit insertion, two penetrators will be separated from the spacecraft
near perilune, one by one, and will be landed on the lunar surface.
The final impact velocity of the penetrator will be about 285 m/sec; it will encounter a shock of about 8000 G at impact on
the lunar surface. According to numerous experimental impact tests using model penetrators and a lunar-regolith analog target,
each penetrator is predicted to penetrate to a depth between l and 3 m, depending on the hardness and/or particle-size distribution
of the lunar regolith. The penetration depth is important for ensuring the temperature stability of the instruments in the
penetrator and heat flow measurements. According to the results of the Apollo heat flow experiment, an insulating regolith
blanket of only 30 cm is sufficient to dampen out about 280 K lunar surface temperature fluctuation to < 3 K variation.
The seismic observations are expected to provide key data on the size of the lunar core, as well as data on deep lunar mantle
structure. The heat flow measurements at two penetrator-landing sites will also provide important data on the thermal structure
and bulk concentrations of heat-generating elements in the Moon. These data will provide much stronger geophysical constraints
on the origin and evolution of the Moon than has been obtained so far.
Currently, the Lunar-A system is being reviewed and a more robust system for communication between the penetrators and spacecraft
is being implemented according to the lessons learned from Beagle-2 and DS-2 failures. More impact tests for penetrators onto
a lunar regolith analogue target will be undertaken before its launch. 相似文献
9.
SMART-1 after lunar capture: First results and perspectives 总被引：1，自引：0，他引：1
B. H. Foing G. D. Racca A. Marini E. Evrard L. Stagnaro M. Almeida D. Koschny D. Frew J. Zender D. Heather M. Grande J. Huovelin H. U. Keller A. Nathues J. L. Josset A. Malkki W. Schmidt G. Noci R. Birkl L. Iess Z. Sodnik P. McManamon 《Journal of Earth System Science》2005,114(6):689-697
SMART-1 is a technology demonstration mission for deep space solar electrical propulsion and technologies for the future.
SMART-1 is Europe’s first lunar mission and will contribute to developing an international program of lunar exploration. The
spacecraft was launched on 27th September 2003, as an auxiliary passenger to GTO on Ariane 5, to reach the Moon after a 15-month
cruise, with lunar capture on 15th November 2004, just a week before the International Lunar Conference in Udaipur. SMART-1
carries seven experiments, including three remote sensing instruments used during the mission’s nominal six months and one
year extension in lunar science orbit. These instruments will contribute to key planetary scientific questions, related to
theories of lunar origin and evolution, the global and local crustal composition, the search for cold traps at the lunar poles
and the mapping of potential lunar resources 相似文献
10.
月球某些资源的开发利用前景 总被引：18，自引：0，他引：18
21世纪月球探测的主要趋势是建立月球基地，开发利用月球的矿产资源，能源和特殊环境，为人类社会的可持续发展发挥长期而有效的支撑作用，通过对月海玄武岩中的钛铁矿，克里普岩中的U，Th,REE和月壤中的拟－3在月面的含量与分布的系统分析，月海玄武碉中蕴藏有极丰富的钛铁矿，TiO2总资源量超过70万亿t，钛铁矿还是月球基地生产水和火箭燃料的主要原料；克里普岩是未来月球探测与研究的热点之一，其蕴藏有巨量的铀，钍，钾，磷和稀土元素资源；月壤长期受到太阳风的辐射，使其蕴藏有极其丰富的氢，氦，氧，氮等气体资源，其中氦－3的资源量大于100万t，它是一种可供人类社会长期使用的，安全，清洁，高效，廉价的核聚变发电燃料，其含量与月壤的化学成分，矿物组分，颗粒大小等有密切的关系。 相似文献
11.
月球表面的地质构造要素主要包括环形构造、线性构造、地体构造及大型盆地构造等。月球大地构造纲要图从物质组成、构造要素、构造单元上对月表的构造状态进行全面的梳理、统计和分析。利用CE 1 CCD 2C像数据、LROC宽视角影像数据、CE 1 IIM 2C干涉成像光谱仪数据、Clementine紫外可见光影像数据、LOLA激光高度计数据识别月球表面各类矿物组分、线形构造、环形构造、火山构造和穹窿构造以及确定构造要素和构造单元的时代、古老撞击坑和大型盆地边界以及对月球表面撞击坑形态、大小、分布、密度及月球断裂和环形影像解译,充分认识月表基本情况,精细划分月表构造地貌单元,综合利用上述分析结果与国际上研究的进展,确定大地构造区划的基本原则,厘定月表重大构造事件与演化序列。依据岩石、月壤、构造地貌与构造形迹的综合分类,拟定大地构造区划的图例、图识规范,确定不同类型环形构造影像、线性构造影像、高地、盆地和月海等大地构造单元,进而编制大地构造区划图,并对重点区域构造形迹进行研究。虹湾区域(LQ 4)月球数字构造编图研究,充分借鉴国际行星地质编图的已有技术标准和规范,结合国内数字地质编图的技术标准和规范,建立了中国自己的月球与行星地质编图标准、规范和制图流程,也为最终完成月球大地构造区划提供地貌和构造方面的基础信息。 相似文献
12.
13.
月球水冰探测进展 总被引：3，自引：0，他引：3
月球上是否存在水冰是第二次月球探测热潮中的热点问题。 1 994年克莱门汀号 (Clementine)环月探测器搭载的频率为 2 .2 73GHz双基地雷达探测到月球南极一些地区出现同向极化增加等独特的回波特征 ,这些地区正好处于极地永久阴影区 ,表明这些地区可能存在水冰。Arecibo天文台频率为 2 .38GHz的地基雷达对月球极地进行制图 ,也得到类似结论。 1 998年月球勘探者号 (LunarProspec tor)环月探测器搭载的中子探测仪在月球极地永久阴影区探测到高含量的氢信号大多认为是水冰引起的。但雷达探测和中子探测结果均存在多解性。月球表面粗糙度同样可以引起雷达回波呈现出类似水冰的异常特征 ,而中子探测仪测量到的仅仅是氢信号而非水 ,而且月球勘探者号撞击月表之后并没有探测到任何的水蒸气信号。月球极地水冰存在与否、存在形式和存在数量等科学问题的回答需要对月球极地特别是永久阴影区作进一步探索 相似文献
14.
Scientific objectives and payloads of Chang’E-1 lunar satellite 总被引：1，自引：0，他引：1
Sun Huixian Dai Shuwu Yang Jianfeng Wu Ji Jiang Jingshan 《Journal of Earth System Science》2005,114(6):789-794
China plans to implement its first lunar exploration mission Chang’E-1 by 2007. The mission objectives are
To achieve the above mission goals, five types of scientific instruments are selected as payloads of the lunar craft. These
include stereo camera and spectrometer imager, laser altimeter, microwave radiometer, gamma and X-ray spectrometers and space
environment monitor system. In order to collect, process, store and transmit the scientific data of various payloads a special
payload data management system is also included. In this paper the goals of Chang’E-1 and its payloads are described 相似文献
| – | • to obtain a three-dimensional stereo image of the lunar surface, |
| – | • to determine distribution of some useful elements and to estimate their abundance |
| – | • to survey the thickness of lunar soil and to evaluate resource of3He and |
| – | • to explore the environment between the Moon and Earth. |
15.
The most fundamental character of lunar soil is its high concentrations of solar-wind-implanted elements, and the concentrations and behavior of the noble gases He, Ne, Ar, and Xe, which provide unique and extensive information about a broad range of fundamental problems. In this paper, the authors studied the forming mechanism of lunar regolith, and proposed that most of the noble gases in lunar regolith come from the solar wind. Meteoroid bombardment controls the maturity of lunar soil, with the degree of maturation decreasing with grain size; the concentrations of the noble gases would be of slight variation with the depth of lunar soil but tend to decrease with grain size. In addition, the concentrations of noble gases in lunar soil also show a close relationship with its mineral and chemical compositions. The utilization prospects of the noble gas ^3He in lunar regolith will be further discussed. 相似文献
16.
17.
Gamma-ray spectrometer(GRS) is used to detect the elemental abundances and distributions on the lunar surface.To derive the elemental abundances,it is vital to acquire background gamma rays except lunar gamma rays.So GRS would observe background spectra in the course of earth-moon transfer on schedule.But in fact,GRS was not switched on in the course of flying toward the moon.After the CE-1 probe finished one-year mission,GRS car-ried out a test on background data on November 21?22,2008.The authors did conduct research on the methods of background deduction using 2105 hours of usable gamma-ray spectra acquired at the 200-km orbital height by the GRS and more than 5 hours of gamma-ray spectra acquired in the GRS background test.The final research results showed that the method of deducting the background using the minimum counts in the CE-1 GRS pixels is optimal for the elements,U,K and Th.The method applies to such a case that the elemental abundances in the pixel with the minimum counting rate are 0 μg/g and the continuum background counts are constant over the Moon.Based on the method of background deduction,the full energy peak counts of U,K,and Th are calculated. 相似文献
18.
19.
Launch strategy for Indian lunar mission and precision injection to the Moon using genetic algorithm
V. Adimurthy R. V. Ramanan S. R. Tandon C. Ravikumar 《Journal of Earth System Science》2005,114(6):711-716
The Indian lunar mission Chandrayaan-1 will have a mass of 523 kg in a 100 km circular polar orbit around the Moon. The main
factors that dictate the design of the Indian Moon mission are to use the present capability of launch vehicles and to achieve
the scientific objectives in the minimum development time and cost. The detailed mission planning involves trade-off studies
in payload optimization and the transfer trajectory determination that accomplishes these requirements. Recent studies indicate
that for an optimal use of the existing launch vehicle and space-craft systems, highly elliptical inclined orbits are preferable.
This indeed is true for the Indian Moon mission Chandrayaan-1. The proposed launch scenario of the Indian Moon mission program
and capabilities of this mission are described in this paper, highlighting the design challenges and innovations. Further,
to reach the target accurately, appropriate initial transfer trajectory characteristics must be chosen. A numerical search
for the initial conditions combined with numerical integration produces the near accurate solution for this problem. The design
of such transfer trajectories is discussed in this paper. 相似文献
20.
我国月球探测的总体科学目标与发展战略 总被引：52，自引：0，他引：52
在简述月球探测的历程与趋势的基础上,强调当代月球探测的总体目标为：①研究月球与地月系的起源和演化,特别是月球大气层与磁场的消失,矿物与岩石的分布和形成环境、月壤和内部层圈结构的形成以及月球演化的历程;②探测月球的资源、能源和特殊环境的开发利用及对人类社会长期可持续发展的支撑。我国不载人月球探测划分为绕、落、回三个阶段。为了全球性、整体性重新认识月球,绕月卫星探测的科学目标是为了获取全月面三维影像,探测14种有用元素的全球分布与丰度,探测月壤厚度并估算氦 3资源量以及太阳活动对空间环境的影响。"落"为月球探测器软着陆就位探测和月球车巡视探测,建立月基光学、低频射电和极紫外天文观测平台。"回"为月球探测器软着陆就位探测和取样返回地面。 相似文献