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The exciting challenge of building a permanent space station has been taken up by the USA, and participation in its development has been offered to the USA's allies. European countries are faced with the dilemma of whether to cooperate or to try to develop an autonomous approach. This article discusses the opportunities for Europe in participating closely in the US project — particularly in providing pressurized modules based on the Columbus programme — and argues that it is an opportunity not to be missed.  相似文献   
2.
This work focuses on the thermo-mechanical design of the microbalance used for the VISTA (Volatile In Situ Thermogravimetry Analyzer) sensor. VISTA has been designed to operate in situ in different space environments (asteroids, Mars, icy satellites). In this paper we focus on its application on Mars, where the expected environmental conditions are the most challenging for the thermo-mechanical design.  相似文献   
3.
An in-depth analysis of the effects exerted on the DNA backbone by 25 crystal phosphate minerals is reported. Degradation of DNA oligomers was performed with two different reactions: Hydrolysis following Nucleophilic Degradation (HND), initiated by the nucleophilic addition of formamide on both purine and pyrimidine nucleobases, and Hydrolysis following Nucleophilic Substitution (HNS) carried on by water and starting with the removal of a nondegraded base. A complete panel of effects on the phosphoester bonds, from protection to enhanced instability to absence of interference, is described. These effects differ in the different degradation pathways and in different physical-chemical conditions. The relationship between the hardness of the mineral and its protective ability is discussed. In addition to its interest per se, this study was prompted by the observed catalytic abilities of soluble and mineral phosphates (Saladino et al., 2006c) on the synthetic reactions by formamide. The relevance of these observations in the search for nonterran life is discussed.  相似文献   
4.
The tracking of large-scale interplanetary (IP) disturbances traveling from the Sun to the Earth is a key issue in space weather studies. The Mexican Array Radio Telescope (MEXART) applies the Interplanetary Scintillation (IPS) technique to detect these solar wind disturbances and it will participate in a global warning network of space weather forecasting. We describe the data storage and computational processes carried out to manage the instrument’s real time data. These procedures are important for the MEXART calibration, operation and the scientific data reduction.  相似文献   
5.
DUSTER (Dust from the Upper Stratosphere Tracking Experiment and Retrieval) is an instrument designed to collect nanometer to micrometer scale solid aerosol particles in the upper stratosphere on board balloons. With three DUSTER flights we have demonstrated that: (1) the instrument’s performance was within the design parameters of environmental specifications (?80 °C; 3–10?mbar); (2) inertial impact collection of aerosols ~500?nm to 24 microns on holey-carbon thin films mounted on Transmission Electron Microscope mesh grids was achieved; (3) the design of an active collector exposed to the air flux and an identical collector “blank”, not exposed to the air flux, to monitor possible contamination permits unambiguous identification of collected particles; (4) save storage of collected samples and subsequent retrieval in the laboratory was achieved with no measurable contamination; (5)?reduced sample manipulation allowed the chemical and structural characterization of collected dust particles by Field-emission scanning electron microscopy and energy dispersive X-Ray analyses, and infrared and Raman micro-spectroscopy. The main and most ambitious goal is the collection and characterization of solid aerosol particles smaller than 3 microns of solar system debris that are currently not sampled on a routine basis by other instruments in the upper stratosphere. DUSTER will provide a record of the amount of solid aerosols, their size, shapes and chemical properties in the upper stratosphere, including particles less than 3 microns in size. The DUSTER program identified 25 particles as collected during the 2008 flight with sizes in the range of 0.4 to 24 microns.  相似文献   
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