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21.
The exploration of space is a long-term endeavor that will require strong public support to weather societal and political changes over the period of its implementation. In August 2006, George Mason University's Center for Aerospace Policy Research organized a workshop to address this issue. The sustainability of space exploration was investigated from a variety of perspectives by invited experts from the space sector as well as from the market research and public relations fields. This paper summarizes the results of the workshop. It presents market research data along with recommendations for an active strategic communications effort as well as public engagement to enhance public support for space exploration, especially among the younger age groups which tend to be uninterested in space activities.  相似文献   
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Crawford IA 《Astrobiology》2010,10(8):853-6; discussion 857-8
Following on from ideas presented in a recent paper by Schneider et al. on "The Far Future of Exoplanet Direct Characterization," I argue that they have exaggerated the technical obstacles to performing such "direct characterization" by means of fast (order 0.1c) interstellar space probes. A brief summary of rapid interstellar spaceflight concepts that may be found in the literature is presented. I argue that the presence of interstellar dust grains, while certainly something that will need to be allowed for in interstellar vehicle design, is unlikely to be the kind of showstopper suggested by Schneider et al. Astrobiology as a discipline would be a major beneficiary of developing an interstellar spaceflight capability, albeit in the longer term, and I argue that astrobiologists should keep an open mind to the possibilities.  相似文献   
24.
We describe the scientific case for and preliminary design of an instrument whose primary goal is to determine the chemistry (element abundance) and mineralogy (compound identity and abundance) of Titan’s surface using a combination of energy dispersive X-ray fluorescence spectroscopy (EDXRF) and X-ray diffraction (XRD). XRD is capable of identifying any crystalline substance present on Titan’s surface at relative abundances greater than ∼1 wt%, allowing unambiguous identification of, for example, structure I and II clathrates (even in the presence of ice), and various organic solids, which may include C2H2, C2H4, C4H2, HCN, CH3CN, HC3N, and C4N2). The XRF component of the instrument will obtain elemental abundances for 16 < Z < 60 with minimum detection limits better than 10 ppm (including detection of atmospheric noble gas isotopes), and may achieve detection limits of 0.01–1% for lighter elements down to Z = 6 (carbon). The instrument is well suited to integration with other analytical tools as part of a light-weight surface chemistry and mineralogy package. Although considerably less sensitive to elemental abundance than GC–MS (10−2 vs. 10−8) it is likely to be significantly lighter (<0.5 kg vs. 10 kg).  相似文献   
25.
Since ESA's establishment the context in which it operates has evolved greatly, from one of development of technologies and general competence to one of responding to the needs of an increasingly wide range of users, many of whose requirements straddle several applications categories. The IAP programme is ESA's response to this challenge, aimed at fostering the growth of a downstream industry, creating a market for the space industry and serving economic growth overall. The programme's structure and the platforms themselves are described and the programme's achievements and prospects presented. Its success testifies to ESA's continuing ability to adapt to changing environments and operate effectively in new sectors.  相似文献   
26.
Space Science Reviews - Modern observatories have revealed the ubiquitous presence of magnetohydrodynamic waves in the solar corona. The propagating waves (in contrast to the standing waves) are...  相似文献   
27.
This paper reviews three important effects on energetic particles of corotating interaction regions (CIRs) in the solar wind that are formed at the leading edges of high-speed solar wind streams originating in coronal holes. A brief overview of CIRs and their important features is followed by a discussion of CIR-associated modulations in the galactic cosmic ray intensity, with an emphasis on observations made by spacecraft particle telescope ‘anti-coincidence’ guards. Such guards combine high counting rates (hundreds of counts/s) and a lower rigidity response than neutron monitors to provide detailed information on the relationship between cosmic ray modulations and CIR structure. The modulation of Jovian electrons by CIRs is then described. Finally, the acceleration of ions to energies of ~20 MeV/n in the vicinity of CIRs is reviewed.  相似文献   
28.
The design and laboratory tests of the interferometers for the Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument which measures thermospheric wind and temperature for the NASA-sponsored Ionospheric Connection (ICON) Explorer mission are described. The monolithic interferometers use the Doppler Asymmetric Spatial Heterodyne (DASH) Spectroscopy technique for wind measurements and a multi-element photometer approach to measure thermospheric temperatures. The DASH technique and overall optical design of the MIGHTI instrument are described in an overview followed by details on the design, element fabrication, assembly, laboratory tests and thermal control of the interferometers that are the heart of MIGHTI.  相似文献   
29.
Materials blasted into space from the surface of early Earth may preserve a unique record of our planet's early surface environment. Armstrong et al. (2002) pointed out that such materials, in the form of terrestrial meteorites, may exist on the Moon and be of considerable astrobiological interest if biomarkers from early Earth are preserved within them. Here, we report results obtained via the AUTODYN hydrocode to calculate the peak pressures within terrestrial meteorites on the lunar surface to assess their likelihood of surviving the impact. Our results confirm the order-of-magnitude estimates of Armstrong et al. (2002) that substantial survivability is to be expected, especially in the case of relatively low velocity (ca. 2.5 km/s) or oblique (相似文献   
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We present here a brief summary of the rich heritage of observational and theoretical research leading to the development of our current understanding of the initiation, structure, and evolution of Coronal Mass Ejections.  相似文献   
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