Venus, Mars, and the ices on Mercury and the moon: astrobiological implications and proposed mission designs

Venus and Mars likely had liquid water bodies on their surface early in the Solar System history. The surfaces of Venus and Mars are presently not a suitable habitat for life, but reservoirs of liquid water remain in the atmosphere of Venus and the subsurface of Mars, and with it also the possibility of microbial life. Microbial organisms may have adapted to live in these ecological niches by the evolutionary force of directional selection. Missions to our neighboring planets should therefore be planned to explore these potentially life-containing refuges and return samples for analysis. Sample return missions should also include ice samples from Mercury and the Moon, which may contain information about the biogenic material that catalyzed the early evolution of life on Earth (or elsewhere). To obtain such information, science-driven exploration is necessary through varying degrees of mission operation autonomy. A hierarchical mission design is envisioned that includes spaceborne (orbital), atmosphere (airborne), surface (mobile such as rover and stationary such as lander or sensor), and subsurface (e.g., ground-penetrating radar, drilling, etc.) agents working in concert to allow for sufficient mission safety and redundancy, to perform extensive and challenging reconnaissance, and to lead to a thorough search for evidence of life and habitability.     

Formation of replicating saponite from a gel in the presence of oxalate: implications for the formation of clay minerals in carbonaceous chondrites and the origin of life

The potential role of clay minerals in the abiotic origin of life has been the subject of ongoing debate for the past several decades. At issue are the clay minerals found in a class of meteorites known as carbonaceous chondrites. These clay minerals are the product of aqueous alteration of anhydrous mineral phases, such as olivine and orthopyroxene, that are often present in the chondrules. Moreover, there is a strong correlation in the occurrence of clay minerals and the presence of polar organic molecules. It has been shown in laboratory experiments at low temperature and ambient pressure that polar organic molecules, such as the oxalate found in meteorites, can catalyze the crystallization of clay minerals. In this study, we show that oxalate is a robust catalyst in the crystallization of saponite, an Al- and Mg-rich, trioctahedral 2:1 layer silicate, from a silicate gel at 60°C and ambient pressure. High-resolution transmission electron microscopy analysis of the saponite treated with octadecylammonium (n(C)=18) cations revealed the presence of 2:1 layer structures that have variable interlayer charge. The crystallization of these differently charged 2:1 layer silicates most likely occurred independently. The fact that 2:1 layer silicates with variable charge formed in the same gel has implications for our understanding of the origin of life, as these 2:1 clay minerals most likely replicate by a mechanism of template-catalyzed polymerization and transmit the charge distribution from layer to layer. If polar organic molecules like oxalate can catalyze the formation of clay-mineral crystals, which in turn promote clay microenvironments and provide abundant adsorption sites for other organic molecules present in solution, the interaction among these adsorbed molecules could lead to the polymerization of more complex organic molecules like RNA from nucleotides on early Earth.     

新一代航天电子系统现场总线及其应用

针对航天电子系统的特殊性,从航天电子系统现场总线技术的发展现状出发,结合现场总线技术的特点,分析了现场总线未来的发展方向。重点介绍了新一代航天电子系统现场总线——有限级联自动重构总线（FCARB）及其在某测量存储系统中的应用。测量存储系统可实现数据并发量10 M,时间同步精度750 ns,系统实时性260 ns。与传统的航天总线相比,新一代现场总线在自动重构、实时性、支持BIT模式、支持仪器总线等方面具有更高的性能,同时对用户更加友好,兼容性更强,能够适应高冲击、高动态等恶劣环境。     

Ballistics, navigation, and motion control for a spacecraft during its landing on the surface of Phobos

Basic concepts and algorithms laid as foundations of the scheme of landing on the Martian moon Phobos (developed for the Phobos-Grunt project) are presented. The conditions ensuring the landing are discussed. Algorithms of onboard navigation and control are described. The equations of spacecraft motion with respect to Phobos are considered, as well as their use for correction of the spacecraft motion. The algorithm of estimation of the spacecraft’s state vector using measurements with a laser altimeter and Doppler meter of velocity and distance is presented. A system for modeling the landing with a firmware complex including a prototype of the onboard computer is described.     

Past, present and future implications of human supervisory control in space missions

Achieving the United States’ Vision for future Space Exploration will necessitate far greater collaboration between humans and automated technology than previous space initiatives. However, the development of methodologies to optimize this collaboration currently lags behind development of the technologies themselves, thus potentially decreasing mission safety, efficiency and probability of success. This paper discusses the human supervisory control (HSC) implications for use in space, and outlines several areas of current automated space technology in which the function allocation between humans and machines/automation is sub-optimal or under dispute, including automated spacecraft landings, Mission Control, and wearable extra-vehicular activity computers. Based on these case studies, we show that a more robust HSC research program will be crucial to achieving the Vision for Space Exploration, especially given the limited resources under which it must be accomplished.     

A new type of magnetic gimballed momentum wheel and its application to attitude control in space

A new type of magnetically suspended gimbal momentum wheel utilizing permanent magnets is described. The bearing was composed of four independent thrust actuators which control the rotor thrust position and gimbal angles cooperatively, so that the bearing comes to have a simple mechanism with high reliability and light weight. The high speed instability problem due to the internal damping was easily overcome by introducing anisotropic radial stiffness. A momentum flywheel with the 3-axis controlled magnetic bearing displays good performance for attitude control of satellite with biased momentum.     

流量调节器研制中的主要问题及结构改进

介绍了一种用于液氧／煤油发动机的流量调节器的结构、原理。在调节器研制中出现的主要问题有滑阀卡滞、主级工况的负载特性存在负差率、转级活塞不能复位等。根据调节器的工作条件,运用静力学原理,分析了产生的原因,提出了改进方法,并进行了试验验证。试验结果表明：结构改进后的调节器工作可靠性得到了明显提高。     

Discovery of abundant cellulose microfibers encased in 250 Ma Permian halite: a macromolecular target in the search for life on other planets

In this study, we utilized transmission electron microscopy to examine the contents of fluid inclusions in halite (NaCl) and solid halite crystals collected 650 m below the surface from the Late Permian Salado Formation in southeastern New Mexico (USA). The halite has been isolated from contaminating groundwater since deposition approximately 250 Ma ago. We show that abundant cellulose microfibers are present in the halite and appear remarkably intact. The cellulose is in the form of 5 nm microfibers as well as composite ropes and mats, and was identified by resistance to 0.5 N NaOH treatment and susceptibility to cellulase enzyme treatment. These cellulose microfibers represent the oldest native biological macromolecules to have been directly isolated, examined biochemically, and visualized (without growth or replication) to date. This discovery points to cellulose as an ideal macromolecular target in the search for life on other planets in our Solar System.     

Disaster assessment and satellite communication: on the threshold of a new era

Disaster events have always been with us. Success or failure of a disaster response is often determined by timely access to communication and the exchange of reliable information. Especially, crucial is information acquired by on-site first responders responsible for initial disaster assessment. The rapid progress in satellite communication development is laying a foundation for a future where lack of communications will no longer be a limiting or paralyzing factor in disaster response. This paper discusses emerging satellite communications tools that can enhance on site assessment and change the way disaster management is viewed and carried out in the next century.     

Multiple generations of carbon in the apex chert and implications for preservation of microfossils

While the Apex chert is one of the most well-studied Archean deposits on Earth, its formation history is still not fully understood. Here, we present Raman spectroscopic data collected on the carbonaceous material (CM) present within the matrix of the Apex chert. These data, collected within a paragenetic framework, reveal two different phases of CM deposited within separate phases of quartz matrix. These multiple generations of CM illustrate the difficulty of searching for signs of life in these rocks and, by extension, in other Archean sequences.     

LOCSS and its implementation on the basis of a small satellite cluster

A problem of providing users with the necessary remote sensing data in the visible and near IR spectral bands has been considered. The solution of the problem plans increase of spatial and spectral resolution for imaging from space, high periodicity of surveying the same sites on the Earth's surface and spaceborne data delivery to users in real time.

This problem solution proposed is to use a cluster of small satellites and to implement the Local Space Service (LOCSS) program. The main aspects of this concept are as follows:

• • optimization of remote sensing instrumentation parameters;

• • image data compression onboard a small spacecraft;

• • compressed data downlinking via the low rate radio channel;

• • direct reception of the image data by users at small cheap receiving stations; and

• • image data decompression and processing using personal computers and special processors.

     

A bacterial enrichment study and overview of the extractable lipids from paleosols in the Dry Valleys, Antarctica: implications for future Mars reconnaissance

The Dry Valleys of Antarctica are one of the coldest and driest environments on Earth with paleosols in selected areas that date to the emplacement of tills by warm-based ice during the Early Miocene. Cited as an analogue to the martian surface, the ability of the Antarctic environment to support microbial life-forms is a matter of special interest, particularly with the upcoming NASA/ESA 2018 ExoMars mission. Lipid biomarkers were extracted and analyzed by gas chromatography--mass spectrometry to assess sources of organic carbon and evaluate the contribution of microbial species to the organic matter of the paleosols. Paleosol samples from the ice-free Dry Valleys were also subsampled and cultivated in a growth medium from which DNA was extracted with the explicit purpose of the positive identification of bacteria. Several species of bacteria were grown in solution and the genus identified. A similar match of the data to sequenced DNA showed that Alphaproteobacteria, Gammaproteobacteria, Bacteriodetes, and Actinobacteridae species were cultivated. The results confirm the presence of bacteria within some paleosols, but no assumptions have been made with regard to in situ activity at present. These results underscore the need not only to further investigate Dry Valley cryosols but also to develop reconnaissance strategies to determine whether such likely Earth-like environments on the Red Planet also contain life.     

Electrification of a rocket during its launch and motion in the atmosphere along active part of the trajectory

We studied the process of electrification of a rocket during launch and flight in the atmosphere at the active part of its trajectory. The values of charge, field strength, and rocket potential at the launch are estimated. Charging and discharging currents are determined for a rocket flying through clouds and precipitation, and solutions expressing the time variation of the rocket’s charge are found. The values of charge, field strength, and rocket potential are obtained as functions of time, together with the engine plume represented as a charged plasma structure. The rocket’s charge is shown to tend to an equilibrium state, and the time of reaching it is found. Mechanisms limiting the charge value are considered, and the conditions of origination of an electric breakdown (lightning) between the rocket and atmosphere are determined.     

按照科学发展观要求深化创新拓展思想政治工作

思想政治工作作为党的建设新的伟大工程的重要组成部分,是我们的优良传统和政治优势。在由计划经济向社会主义市场经济转型的过程中,任何企图削弱或取消思想政治工作的观点和做法,都是错误和有害的;然而思想政治工作如果不面对新形势新情况,完成由传统形态向现代形态的转换,也将不能发挥其应有的作用。在新形势下,做好新时期思想政治工作,认真研究新形势下思想政治工作的特点和规律,     

张大千泼墨泼彩成因蠡测

“泼墨泼彩”法是张大千最大的艺术创造,是20世纪中国绘画发展的重要成果之一。论文从内因和外因两方面对张大千泼墨泼彩画的形成原因进行分析。生性豪放,“无不造其极”的个性,熔铸古今、临摹万轴名画的工夫,眼疾无奈,顺势而就是其泼墨泼彩的三大内因;古法启示,中西画法对比,迎合市场需求是其泼墨泼彩的三大外因。     

Living in space: scientific, medical and cultural implications. A selection of papers presented at the 14th IAA Humans in Space Symposium

The Humans In Space 2003 symposium, entitled "Living in Space: Scientific, Medical and Cultural Implications," was sponsored by the Canadian Space Agency and held in Banff, Alberta, from May 18-22, 2003. There were 150 papers presented in six theme areas: education, missions, physiology, psychology, radiation, and technology. The 32 papers in this volume are organized into Education/Outreach, Medical Care (Bedrest), Medical Care (Countermeasures), Medical Care, Missions (Mars), Missions (Neurolab), Missions (Historical Lessons), Physiology, Psychology, Radiation, Technology (Human Factors), and Technology.     

Smaller states and the new balance of power in space

The number of states capable of building, launching and operating satellites has grown significantly over the years. This article discusses how going to space in an egalitarian fashion may influence the current state of affairs related to the militarization and weaponization of outer space, the security postures of the already established space powers, and the global balance of power in general. Potential changes in the relationship between old and new spacefarers may instigate an entire shift in the understanding of threats and opportunities for international cooperation in space.     

转变观念强化管理提高能力狠抓落实努力开创航天产品制造工艺新局面--张庆伟总经理在集团公司第一次工艺工作会上的讲话摘要

2005年9月26日,中国航天科技集团公司召开了第一次工艺工作会议。会议由张丽辉总经理助理主持,集团公司总经理张庆伟做了重要讲话,许达哲副总经理做了工作报告。张庆伟总经理在讲话中强调:今后的工艺工作要强化“一个意识”,提高“两个能力”,把握“三个结合”,培养“四个能力”,抓好“五项工作”。他明确指出:“工艺是核心竞争力,是重要的生产力”。要完成“十一五”期间的科研生产任务,必须提高关键工艺技术的攻关能力与工艺基础能力。工艺作为制造的核心,工艺水平必须要有一个大的跨越,因此,对于工艺工作,要做好设计和工艺的结合、工艺技术与工艺管理的结合、工艺与信息化的结合。为了更好地学习、宣传、贯彻中国航天科技集团公司第一次工艺工作会议精神,本刊特辟专栏摘要刊登张庆伟总经理、许达哲副总经理的重要讲话。     

A study of evolution of spin-up mode of a satellite in the plane of its orbit

We investigate the mode of spinning up a low-orbit satellite in the plane of its orbit. In this mode the satellite rotates around its principal central axis of the minimum moment of inertia which executes small oscillations with respect to the normal to the orbit plane; the angular velocity of the rotation around this axis several times exceeds the mean orbital motion. Gravitational and restoring aerodynamic moments are taken into account in the satellite’s equations of motion. A small parameter characterizing deviation of the satellite from a dynamically symmetric shape is introduced into the equations. A two-dimensional integral surface of the equations of motion, describing quasi-steady-state rotations of the satellite close to cylindrical precession of the corresponding symmetrical satellite in a gravitational field, has been studied by the method of small parameter and numerically. Such quasi-steady-state rotations are suggested to be considered as unperturbed motions of the satellite in the spin-up mode. Investigation of the integral surface is reduced to numerical solution of a periodic boundary value problem of a certain auxiliary system of differential equations and to calculation of quasi-steady-state rotations by the two-cycle method. A possibility is demonstrated to construct quasi-steady rotations by way of minimization of a special quadratic functional.