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31.
A new experimental approach is discussed in general terms, that can be adopted in the Shuttle/Spacelab era starting in the 1980s for studies in the area of plasma flow interactions with bodies in space. The potential use of the Space Shuttle/Orbiter as a near Earth plasma laboratory for studies in the area of Space Plasma Physics and particularly in the area of Solar-System Plasmas is discussed. This new experimental approach holds great promise for studies in the Supersonic and sub-Alfvenic flow regime which has applications to the motion of natural satellites around their mother planets in the Solar-system (e.g. the satellite Io around the planet Jupiter). A well conceived experimental and theoretical program, can lead to a better physical understanding regarding the validity and range of applicability of using gas-dynamic, kinetic and fluid approaches in describing collisionless plasma flow interactions with bodies in a variety of flow regimes.In addition to the above scientific aspects of the program, significant technological advances can be achieved regarding the interaction of space probes in planetary atmospheres/ionospheres and the reliability of using various plasma diagnostic devices on board spacecraft and large space platforms. 相似文献
32.
The International Space Station will provide an extremely high-quality, long-duration microgravity environment for the conduct of research. In addition, the ISS offers a platform for performing observations of Earth and Space from a high-inclination orbit, outside of the Earth's atmosphere. This unique environment and observational capability offers the opportunity for advancement in a diverse set of research fields. Many of these disciplines do not relate to one another, and present widely differing approaches to study, as well as different resource and operational requirements. Significant challenges exist to ensure the highest quality research return for each investigation. Requirements from different investigations must be identified, clarified, integrated and communicated to ISS personnel in a consistent manner. Resources such as power, crew time, etc. must be apportioned to allow the conduct of each investigation. Decisions affecting research must be made at the strategic level as well as at a very detailed execution level. The timing of the decisions can range from years before an investigation to real-time operations. The international nature of the Space Station program adds to the complexity. Each participating country must be assured that their interests are represented during the entire planning and operations process. A process for making decisions regarding research planning, operations, and real-time replanning is discussed. This process ensures adequate representation of all research investigators. It provides a means for timely decisions, and it includes a means to ensure that all ISS International Partners have their programmatic interests represented. 相似文献
33.
G. Randall Gladstone S. Alan Stern Kurt D. Retherford Ronald K. Black David C. Slater Michael W. Davis Maarten H. Versteeg Kristian B. Persson Joel W. Parker David E. Kaufmann Anthony F. Egan Thomas K. Greathouse Paul D. Feldman Dana Hurley Wayne R. Pryor Amanda R. Hendrix 《Space Science Reviews》2010,150(1-4):161-181
34.
U. Feldman 《Space Science Reviews》1998,85(1-2):227-240
Recent spectroscopic measurements from instruments on the Solar and Heliospheric Observatory (SOHO) find that the coronal
composition above a polar coronal hole is nearly photospheric. However, similar SOHO observations show that in coronal plasmas
above quiet equatorial regions low-FIP elements are enhanced by a factor of ≈ 4. In addition, the process of elemental settling
in coronal plasmas high above the solar surface was shown to exist. Measurements by the Ulysses spacecraft, which are based
on non-spectroscopic particle counting techniques, show that, with the exception of He, the elemental composition of the fast
speed solar wind is similar to within a factor of 1.5 to the composition of the photosphere. In contrast, similar measurements
in the slow speed wind show that elements with low first ionization potential (FIP < 10 eV) are enhanced, relative to the
photosphere, by a factor of 4-5. By combining the SOHO and Ulysses results, ideas related to the origin of the slow speed
solar wind are presented. Using spectroscopic measurements by the Solar Ultraviolet Measurement of Emitted Radiation (SUMER)
instrument on SOHO the photospheric abundance of He was determined as 8.5 ± 1.3% (Y = 0.248).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献