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Emilie Habart Malcolm Walmsley Laurent Verstraete Stephanie Cazaux Roberto Maiolino Pierre Cox Francois Boulanger Guillaume Pineau Des Forêts 《Space Science Reviews》2005,119(1-4):71-91
Observations of H2 line emission in galactic and extragalactic environments obtained with the Infrared Space Observatory (ISO) are reviewed.
The diagnostic capability of H2 observations is illustrated. We discuss what one has learned about such diverse astrophysical sources as photon-dominated
regions, shocks, young stellar objects, planetary nebulae and starburst galaxies from ISO observations of H2 emission. In this context, we emphasise use of measured H2 line intensities to infer important physical quantities such as the gas temperature, gas density and radiation field and
we discuss the different possible excitation mechanisms of H2. We also briefly consider future prospects for observation of H2 from space and from the ground.
Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries:
France, Germany, The Netherlands, and the United Kingdom), and with the participation of ISAS and NASA. 相似文献
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This paper first gives an overview of the applications of micro-electro-mechanical systems (MEMS) in space. Microsystems are advertised for their extremely low size and mass, along with their low power consumption and in some case their improved performances. Examples of actual flown MEMS and future missions relying on MEMS are given. Microsystems are now enjoying a dynamic and expanding interest in the space community. This paper intends to give an idea about the next step in miniaturization, since the microelectronic industry is already looking at nano-electro-mechanical systems (NEMS) driven by the more-than-Moore philosophy. We show that the impact of nanosystems should not be reduced at a homothecy in size, weight and power consumption. New forces appear at this scale (Casimir force…) which have to be considered in the system design. The example of a nano-mechanical memory is developed. We also show that performances of nanosystems are not systematically better than their microscopic counterparts through the study of the impact of dimension reduction on an accelerometer resolution and sensitivity. We conclude with the idea that nanosystems will find their greatest applications in distributed intelligent networks that will allow new mission concepts for space exploration. 相似文献
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Laurent Vigroux Pascal Gallais Marc Sauvage Harley Thronson Jr. 《Space Science Reviews》1995,74(1-2):xi-xii