Survival of spores of the UV-resistant Bacillus subtilis strain MW01 after exposure to low-earth orbit and simulated martian conditions: data from the space experiment ADAPT on EXPOSE-E

In the space experiment "Molecular adaptation strategies of microorganisms to different space and planetary UV climate conditions" (ADAPT), bacterial endospores of the highly UV-resistant Bacillus subtilis strain MW01 were exposed to low-Earth orbit (LEO) and simulated martian surface conditions for 559 days on board the European Space Agency's exposure facility EXPOSE-E, mounted outside the International Space Station. The survival of B. subtilis MW01 spores from both assays (LEO and simulated martian conditions) was determined by a colony-formation assay after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110?nm) as well as the martian UV spectrum (λ≥200?nm) was the most deleterious factor applied; in some samples only a few spore survivors were recovered from B. subtilis MW01 spores exposed in monolayers. However, if shielded from solar irradiation, about 8% of MW01 spores survived in LEO conditions, and 100% survived in simulated martian conditions, compared to the laboratory controls. The results demonstrate the effect of shielding against the high inactivation potential of extraterrestrial solar UV radiation, which limits the chances of survival of even the highly UV-resistant strain of B. subtilis MW01 in the harsh environments of outer space and the martian surface.     

高活性铝粉的改性及在化学推进剂中 燃烧团聚研究进展

通过添加金属粉来提高化学火箭推进剂的能量性能已成为一种通用方法,但在实际应用中存在一系列利弊的两方面问题。研究了不同类型铝粉的活化和活性铝粉(包括球形μAl、包覆n Al、化学活化和机械活化铝粉)的特性,考察了其对推进剂燃烧性能的改善和聚集/团聚机理,并提出了提高铝粉燃烧效能的方法途径。结果表明,纳米铝粉不仅可显著提高推进剂的燃速,还可使推进剂的凝相燃烧产物(CCP)明显减少,从而减少两相流损失;活化Al尽管会降低Is,但其活性Al含量所产生的理论Is比n Al的高,尤其是机械活化铝粉。由于不同活化铝粉具有各自的优缺点,建议同时搭配使用两种不同类型的活化铝粉,以弥补单一铝粉的缺点。     

Pc5 Oscillation Analysis by the Satellite and Ground-Based Data

Large amplitude Pc5 event was observed in the space and on ground on August 3, 2001, about three hours after contact of the strong discontinuity in the solar wind with the magnetosphere according to data from ACE and Wind satellites. The Pc5 amplitude was as high as 15 nT in the tail of magnetosphere and about 5 nT at the ground based stations. In the magnetosphere Pc5 waves were observed by Cluster and Polar satellites, which occupied positions in the morning part of the near tail at the close field lines but were parted by distance of 11.5 Re, mainly along the x-axis of the GSM coordinate system. Both compressional and transverse components of the Pc5 wave activity were observed in the space, with the transverse component having the larger amplitude. Time delay between the Cluster and Polar satellites was about 8 minutes, which could be interpreted as a wave propagation from the geomagnetic tail to the Earth with the 150 km/s group velocity. The ground-based Pc5 activity was analysed by using data from the Image magnetometer network. Doubtless demonstrations of a field line resonant structure were found in variations of amplitude and polarization with latitude. Finnish chain of search coil magnetometers observed modulated Pc1 emission simultaneously with the Pc5 wave train. A possibility of non-linear impact of Pc5 wave energy on the plasma and waves in the magnetosphere is discussed.     

The Main Results and the Perspectives in the Researches at SSRT

In this report briefly presented the contemporary state of the experimental base of Radio Astrophysical Observatory (RAO) of the Institute of Solar-Terrestrial Physics (ISTP), the methodology of radioheliographic monitoring of the solar corona, the SSRT database, the RAO Web-pages, factors limiting the effective use of SSRT. Here are formulated the original results of the basic directions of the solar activity researches and the problems solutions on SSRT: (1) active regions at various development stages, morphology, modeling,signs of energy accumulation and flares buildup, forecast of powerful flares; (2) scenario, topology and the fine temporal picture of flares development, signs of primary energy release, radio emission mechanisms, scatter effects of radio emission in turbulent corona, energetic particles fluxes; (3) filaments; (4) CME with the localization of their initiation at the solar disk background, development scenario of filament activation + CME +flare; (5) coronal holes, and (6) bright coronal points.      

Science Missions Using CubeSats

As the role of missions and experiments carried out in outer space becomes more and more essential in our understanding of many earthly problems, such as resource management, environmental problems, and disaster management, as well as space science questions, thanks to their lower cost and faster development process CubeSats can benefit humanity and therefore, young scientists and engineers have been motivated to research and develop new CubeSat missions. Not very long after their inception, CubeSats have evolved to become accepted platforms for scientific and commercial applications. The last couple of years showed that they are a feasible tool for conducting scientific experiments, not only in the Earth orbit but also in the interplanetary space. For many countries, a CubeSat mission could prompt the community and young teams around the world to build the national capacity to launch and operate national space missions. This paper presents an overview of the key scientific and engineering gateways opened up to the younger scientific community by the advent and adaptation of new technology into CubeSat missions. The role of cooperation and the opportunities for capacity-building and education are also explored. Thus, the present article also aims to provide useful recommendations to scientists, early-career researchers, engineers, students, and anyone who intends to explore the potential and opportunities offered by CubeSats and CubeSats-based missions.      

航天飞机指控中心Unix工作站中专家系统的实时数据获取

最具代表性的美国技术杰作之一可能是位于德克萨斯州休斯顿的约翰逊航天中心的航天指挥控制中心(MCC)。该中心各指挥室经历了美国技术史上许多重大事件,如首次登月、营救天空实验室以及首次发射航天飞机。60年代初MCC首次启用时,的确是技术杰作。然而该设施自阿波罗任务后只进行过不大的改进。直到最近,它仍然维持着以单主机的结构,     

设计测取精度信息的导弹飞行试验计划用的统计方法

决定导弹飞行试验计划测得精度能力的因素有:被试系统(即惯性制导系统、天文导航系统等)的误差模型;测量系统(即外测系统、遥测等)的误差模型;数据精度;飞行试验前得到的先验信息;弹道(或轨道)以及数据分析的方法。这些因素可以用数字计算机进行仿真,并且可以借助加权最小二乘回归法对具体的精度值求得定量的统计指标。在设计试验计划阶段,数字仿真和统计分析可用来进行综合研究,以便使弹道、测量系统和飞行前试验计划要求等试验条件达到最佳。通过正确的试验设计,常常可以把飞行试验计划测量精度的能力提高10-100倍。     

Navigation sensors and systems in GNSS degraded and denied environments

Position, velocity, and timing(PVT) signals from the Global Positioning System(GPS)are used throughout the world but the availability and reliability of these signals in all environments has become a subject of concern for both civilian and military applications. This presentation summarizes recent advances in navigation sensor technology, including GPS, inertial, and other navigation aids that address these concerns. Also addressed are developments in sensor integration technology with several examples described, including the Bluefin-21 system mechanization.