Input Parameters for Models of Energetic Electrons Fluxes at the Geostationary Orbit

The results of cross-correlation analysis between electrons fluxes (with energies of > 0.6MeV, > 2.0 MeV and > 4.0MeV), geomagnetic indices and solar wind parameters are shown in the paper. It is determined that the electron fluxes are controlled not only by the geomagnetic indices, but also by the solar wind parameters, and the solar wind velocity demonstrates the best relation with the electron fluxes. Numerical value of the relation efficiency of external parameters with the highly energetic electrons fluxes shows a periodicity. It is presented here the preliminary results of daily averaged electrons fluxes forecast for a day ahead on the basis of the model of neuron networks.     

The Urey instrument: an advanced in situ organic and oxidant detector for Mars exploration

The Urey organic and oxidant detector consists of a suite of instruments designed to search for several classes of organic molecules in the martian regolith and ascertain whether these compounds were produced by biotic or abiotic processes using chirality measurements. These experiments will also determine the chemical stability of organic molecules within the host regolith based on the presence and chemical reactivity of surface and atmospheric oxidants. Urey has been selected for the Pasteur payload on the European Space Agency's (ESA's) upcoming 2013 ExoMars rover mission. The diverse and effective capabilities of Urey make it an integral part of the payload and will help to achieve a large portion of the mission's primary scientific objective: "to search for signs of past and present life on Mars." This instrument is named in honor of Harold Urey for his seminal contributions to the fields of cosmochemistry and the origin of life.     

The astrobiology primer: an outline of general knowledge--version 1, 2006

The Astrobiology Primer has been created as a reference tool for those who are interested in the interdisciplinary field of astrobiology. The field incorporates many diverse research endeavors, but it is our hope that this slim volume will present the reader with all he or she needs to know to become involved and to understand, at least at a fundamental level, the state of the art. Each section includes a brief overview of a topic and a short list of readable and important literature for those interested in deeper knowledge. Because of the great diversity of material, each section was written by a different author with a different expertise. Contributors, authors, and editors are listed at the beginning, along with a list of those chapters and sections for which they were responsible. We are deeply indebted to the NASA Astrobiology Institute (NAI), in particular to Estelle Dodson, David Morrison, Ed Goolish, Krisstina Wilmoth, and Rose Grymes for their continued enthusiasm and support. The Primer came about in large part because of NAI support for graduate student research, collaboration, and inclusion as well as direct funding. We have entitled the Primer version 1 in hope that it will be only the first in a series, whose future volumes will be produced every 3-5 years. This way we can insure that the Primer keeps up with the current state of research. We hope that it will be a great resource for anyone trying to stay abreast of an ever-changing field.     

可替代机械陀螺的光纤速率陀螺

光纤陀螺在两个方面正在取代机械陀螺：一是新设计的应用，二是已有的应用陀螺场合。光学陀螺所具有的高可靠性、对重力g的不敏感性和对振动、冲击的容限，使其特别适合于车辆、军事上的应用。基于Sagnac干涉效应，如环形激光陀螺、光纤陀螺的概论已有十十年之久了。它有闭环和开环两种结构，但由于闭环结构成本较高，目前只利用开环光纤陀螺取代机械速率陀螺。我们开发了一系列低成本光纤陀螺，它们基于全光结构，采用椭芯的保偏光纤、方向耦合器和偏振器。开环光纤陀螺是以最小结构的形式构成的。激光光束在光纤敏感相向传输，它们是完全互逆的。早期的形式采用方向耦合器隔离激光光源和光探测器，一个偏振器用来确保一个模式分布，而第二个耦合器作为与光纤环的接入口，在光纤环的一端加上一个压电陶瓷相位调制器以进行调制，以便同步检测干涉仪的输出。光源探测器处的耦合器不属于最小结构中的一部分，它可以通过用光源的反向的探测器取消。目前许多激光光源被用于这样一个探测光输出的探测器，由于陀螺转动信号是调制信号，很容易与恒定的激光输出信号分开。我们这种结构的FOG为简化最小结构（RMC），比较两种开环结构可以看出：两者之间没有明显的区别，但从性质上分，在RMC结构中，激光器工作在接近阈值的点，因而在光谱上比较窄。在光陀螺中希望有一个宽带的光谱，可以避免由于绕环导致的偏振起伏，从而引起偏置的不稳定性。这也就限定了RMC结构在一些高精度的陀螺应用。光纤陀的特性可以通过选择光纤的长度、环的直径和激光功率在一个比较大的范围内调整，以适应不同的应用要求，而不需要改变其结构。光纤陀螺从本性上为宽带的，其输出谱特性可以由简单的模拟滤波器、扩展伺服回路的动态特性加以控制。与简单的机械陀螺相比，这一宽带特性可以扩展为非常低的频率，从而改善定位精度。我们已生产了1000多套这两种结构的光纤陀，本文将提供Allan变化，随温度变化的偏置、刻度因数的线性数据，典型的特性参数如下：也许光纤陀螺应用最大的限制为刻度系数，因为Sagnac干涉仪的灵敏度领先光纤长度乘以直径，并且几何尺寸和在敏感轴垂直平面上投影使光纤陀螺改型应用的困难得以克服。在带宽限制范围内，光纤陀螺可以在众多的系统中应用。     

Investigation of low-energy proton effects on aptamer performance for astrobiological applications

Biochips are promising instruments for the search for organic molecules in planetary environments. Nucleic acid aptamers are powerful affinity receptors known for their high affinity and specificity, and therefore are of great interest for space biochip development. A wide variety of aptamers have already been selected toward targets of astrobiological interest (from amino acids to microorganisms). We present a first study to test the resistance of these receptors to the constraints of the space environment. The emphasis is on the effect of cosmic rays on the molecular recognition properties of DNA aptamers. Experiments on beam-line facilities have been conducted with 2 MeV protons and fluences much higher than expected for a typical mission to Mars. Our results show that this irradiation process did not affect the performances of DNA aptamers as molecular recognition tools.     

Damage escape and repair in dried Chroococcidiopsis spp. from hot and cold deserts exposed to simulated space and martian conditions

The cyanobacterium Chroococcidiopsis, overlain by 3?mm of Antarctic sandstone, was exposed as dried multilayers to simulated space and martian conditions. Ground-based experiments were conducted in the context of Lichens and Fungi Experiments (EXPOSE-E mission, European Space Agency), which were performed to evaluate, after 1.5 years on the International Space Station, the survival of cyanobacteria (Chroococcidiopsis), lichens, and fungi colonized on Antarctic rock. The survival potential and the role played by protection and repair mechanisms in the response of dried Chroococcidiopsis cells to ground-based experiments were both investigated. Different methods were employed, including evaluation of the colony-forming ability, single-cell analysis of subcellular integrities based on membrane integrity molecular and redox probes, evaluation of the photosynthetic pigment autofluorescence, and assessment of the genomic DNA integrity with a PCR-based assay. Desiccation survivors of strain CCMEE 123 (coastal desert, Chile) were better suited than CCMEE 134 (Beacon Valley, Antarctica) to withstand cellular damage imposed by simulated space and martian conditions. Exposed dried cells of strain CCMEE 123 formed colonies, maintained subcellular integrities, and, depending on the exposure conditions, also escaped DNA damage or repaired the induced damage upon rewetting.     

The O/OREOS mission: first science data from the Space Environment Survivability of Living Organisms (SESLO) payload

We report the first telemetered spaceflight science results from the orbiting Space Environment Survivability of Living Organisms (SESLO) experiment, executed by one of the two 10?cm cube-format payloads aboard the 5.5?kg Organism/Organic Exposure to Orbital Stresses (O/OREOS) free-flying nanosatellite. The O/OREOS spacecraft was launched successfully to a 72° inclination, 650?km Earth orbit on 19 November 2010. This satellite provides access to the radiation environment of space in relatively weak regions of Earth's protective magnetosphere as it passes close to the north and south magnetic poles; the total dose rate is about 15 times that in the orbit of the International Space Station. The SESLO experiment measures the long-term survival, germination, and growth responses, including metabolic activity, of Bacillus subtilis spores exposed to the microgravity, ionizing radiation, and heavy-ion bombardment of its high-inclination orbit. Six microwells containing wild-type (168) and six more containing radiation-sensitive mutant (WN1087) strains of dried B. subtilis spores were rehydrated with nutrient medium after 14 days in space to allow the spores to germinate and grow. Similarly, the same distribution of organisms in a different set of microwells was rehydrated with nutrient medium after 97 days in space. The nutrient medium included the redox dye Alamar blue, which changes color in response to cellular metabolic activity. Three-color transmitted intensity measurements of all microwells were telemetered to Earth within days of each of the 48?h growth experiments. We report here on the evaluation and interpretation of these spaceflight data in comparison to delayed-synchronous laboratory ground control experiments.     

利用卫星实现与飞行中巡航导弹的通信

本文讨论了与飞行中远程巡航导弹通信的需求以及卫星作为中继平台的潜力。国防卫星通信系统Ⅲ(DSCSⅢ）和舰队卫星通信（FLTSATCOM）星至少能够同时为70枚巡航导弹向水面舰只和陆基指挥中心传送200bit的状态信息。DSCSⅢ还可以同是为至少70枚巡航导弹提供准实时有人末制导支持（只要巡航导弹装有共影天线阵）。FLTSATCOM可以为2枚装有全向天线阵的巡航导弹提供相同的能力。这种能力包括传统末段敏感器图象数据，该图象数据的速率为每格每秒40kbits,取决于可实现的图象数据压缩比。本文还论述了指挥员利用这些系统重新瞄准新目标，允许一枚巡航导弹向地面传送一路末段敏感器图象。