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91.
Christopher J. Mertens Jeremy R. Winick Richard H. Picard David S. Evans Manuel López-Puertas Peter P. Wintersteiner Xiaojing Xu Martin G. Mlynczak James M. Russell III 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Thermospheric infrared radiance at 4.3 μm is susceptible to the influence of solar-geomagnetic disturbances. Ionization processes followed by ion-neutral chemical reactions lead to vibrationally excited NO+ (i.e., NO+(v)) and subsequent 4.3 μm emission in the ionospheric E-region. Large enhancements of nighttime 4.3 μm emission were observed by the TIMED/SABER instrument during the April 2002 and October–November 2003 solar storms. Global measurements of infrared 4.3 μm emission provide an excellent proxy to observe the nighttime E-region response to auroral dosing and to conduct a detailed study of E-region ion-neutral chemistry and energy transfer mechanisms. Furthermore, we find that photoionization processes followed by ion-neutral reactions during quiescent, daytime conditions increase the NO+ concentration enough to introduce biases in the TIMED/SABER operational processing of kinetic temperature and CO2 data, with the largest effect at summer solstice. In this paper, we discuss solar storm enhancements of 4.3 μm emission observed from SABER and assess the impact of NO+(v) 4.3 μm emission on quiescent, daytime retrievals of Tk/CO2 from the SABER instrument. 相似文献
92.
Hugh C. Pumphrey Richard E. Cofield Mark J. Filipiak Nathaniel J. Livesey 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Microwave Limb Sounder (MLS) instrument is a small satellite-borne radio telescope. Its purpose is to make limb-scanning measurements of atmospheric composition. One of the gases to which it is sensitive is carbon monoxide (CO), detected via the J = 2 → 1 rotational transition at 230 GHz. CO is present in molecular gas clouds in the Milky Way. Although it was not designed for the purpose, MLS can detect emissions from galactic CO, allowing a map of the 230 GHz radio sky to be constructed. We report the MLS measurements of galactic radio emission and discuss their effect on the atmospheric mission of MLS. The region of the Milky Way with emissions strong enough to significantly affect MLS observations of atmospheric CO is identified. Ground-based radio astronomers have been mapping the sky using CO emission for many years. However, the MLS data are the first such survey to be carried out from space. The MLS survey covers a larger area of the sky than any other 230 GHz survey, but no previously unknown gas clouds are observed. 相似文献
93.
This paper describes and analyses the economics of a power relay system that takes advantage of recent technological advances to implement a system that is economically viable. A series of power relay systems are described which transport power ranging from 1250 to 5000 MW and distribute it to receiving sites at transcontinental distances. It is shown that, when offering electricity at prices competitive to those prevalent in developed cities in the USA, that a low IRR is inevitable, and economic feasibility of a business is unlikely. However, when the target market is Japan, where the prevalent electricity prices are much higher an IRR exceeding 65% is readily attainable. This is extremely attractive to potential investors, making capitalization of a venture likely. The paper shows that the capital investment required for the system can be less than $1 per installed watt, contributing less than 0.02 $ to the cost of energy provision. Since selling prices in feasible regions range from 0.18 to over 0.30 $, these costs are but a small fraction of the operating expenses. Thus a very large IRR is possible for such a business. 相似文献
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96.
The results of a study by MMS for BNSC and the UK Meteorological Office into the potential use of Smallsats to support METOP are reported. A risk of degradation or failure of a mission critical instrument during the METOP lifetime has been identified. The scenario proposed uses a Smallsat flying in formation with METOP to replace a failed instrument with data being returned to METOP via an inter-satellite link. An assessment of small launcher and small platform availability and instrument interface requirements indicates that such a scenario is feasible. Minor modifications to METOP and a relative pointing correction during ground processing would be required. It is concluded that a Smallsat could provide a significant improvement to METOP programme reliability with low design and cost risk. Scenario attractiveness depends upon whether a critical instrument failure would justify replacement. 相似文献
97.
André Balogh Andrei Bykov Peter Cargill Richard Dendy Thierry Dudok de Wit John Raymond 《Space Science Reviews》2013,178(2-4):77-80
With the maturing of space plasma research in the solar system, a more general approach to plasma physics in general, applied to cosmic plasmas, has become appropriate. There are both similarities and important differences in describing the phenomenology of space plasmas on scales from the Earth’s magnetosphere to galactic and inter-galactic scales. However, there are important aspects in common, related to the microphysics of plasma processes. This introduction to a coordinated collection of papers that address the several aspects of the microphysics of cosmic plasmas that have unifying themes sets out the scope and ambition of the broad sweep of topics covered in the volume, together with an enumeration of the detailed objectives of the coverage. 相似文献
98.
Richard S. Mussakowski 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(8):103-107
This paper describes a procedure for detecting and mapping changes in vegetation cover using LANDSAT digital analysis techniques, and demonstrates how the procedure can be used as an aid to environmental monitoring. Digital image analysis is used to perform a historical comparison, and a computerized colour plotter is used to map the changes in vegetation. 相似文献
99.
Adigun Ade Abiodun Richard S. Odingo 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(7):79-84
Through space applications, a number of social and economic programmes in education, communications, agro-climatology, weather forecasting and remote sensing are being realized within the African continent. Regional and international organizations and agencies such as the African Remote Sensing Council, the Pan-African Telecommunication Union and the United Nations system have been instrumental in making Africa conscious of the impact and implications of space science and technology on its peoples.The above notwithstanding, discernible interests in space research, to date, in Africa, have been limited to the work on the solar system and on interplanetary matters including satellite tracking, and to the joint African-Indian proposal for the establishment of an International Institute for Space Sciences and Electronics (INISSE) and the construction, in Kenya, of a Giant Equatorial Radio Telescope (GERT).During this “Transport and Communications Decade in Africa,” Africa's basic space research efforts would need to initially focus on the appropriateness, modification and adaptation of existing technologies for African conditions with a view to providing economic, reliable and functional services for the continent. These should include elements of electronics, communications, structural and tooling industries, and upper-atmosphere research. The experience of and collaborative work with India, Brazil and Argentina, as well as the roles of African scientists, are examined. 相似文献
100.