The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
D E Larson - One of the best experts on this subject based on the ideXlab platform.
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quantitative prediction of radiation belt electrons at Geostationary Orbit based on solar wind measurements
Geophysical Research Letters, 2001Co-Authors: X Li, M Temerin, D N Baker, G D Reeves, D E LarsonAbstract:Solar wind measurements are used to predict the MeV electron radiation belt flux at the position of Geostationary Orbit. Using a model based on the standard radial diffusion equation, a prediction efficiency of 0.81 and a linear correlation of 0.90 were achieved for the years 1995–1996 for the logarithm of average daily flux. Model parameters based on the years 1995-1996 gave a prediction efficiency and a linear correlation for the years 1995–1999 of 0.59 and 0.80, respectively. The radial diffusion equation is solved after making the diffusion coefficient a function of the solar wind velocity and interplanetary magnetic field. The solar wind velocity is the most important parameter governing relativistic electron fluxes at Geostationary Orbit. The model also provides a physical explanation to several long standing mysteries of the variation of the MeV electrons.
X Li - One of the best experts on this subject based on the ideXlab platform.
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quantitative prediction of radiation belt electrons at Geostationary Orbit based on solar wind measurements
Geophysical Research Letters, 2001Co-Authors: X Li, M Temerin, D N Baker, G D Reeves, D E LarsonAbstract:Solar wind measurements are used to predict the MeV electron radiation belt flux at the position of Geostationary Orbit. Using a model based on the standard radial diffusion equation, a prediction efficiency of 0.81 and a linear correlation of 0.90 were achieved for the years 1995–1996 for the logarithm of average daily flux. Model parameters based on the years 1995-1996 gave a prediction efficiency and a linear correlation for the years 1995–1999 of 0.59 and 0.80, respectively. The radial diffusion equation is solved after making the diffusion coefficient a function of the solar wind velocity and interplanetary magnetic field. The solar wind velocity is the most important parameter governing relativistic electron fluxes at Geostationary Orbit. The model also provides a physical explanation to several long standing mysteries of the variation of the MeV electrons.
C Portmann - One of the best experts on this subject based on the ideXlab platform.
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status of cnes optical observations of space debris in Geostationary Orbit
Advances in Space Research, 2004Co-Authors: F Alby, M Boer, B Deguine, I Escane, F Newland, C PortmannAbstract:Abstract On-ground optical systems using a telescope and a CCD camera offer an effective solution to the problem of observing objects in Geostationary Orbit. CNES has been studying and developing such systems for several years with two main objectives: firstly to develop systems able to detect debris in the vicinity of the Geostationary Orbit for statistical evaluation of the population and secondly to develop a tool to determine the Orbits accurately: these objectives are currently met using two different systems called TAROT and ROSACE. This paper presents the main characteristics of both systems, the principle of their image processing software, their development status and the main results obtained. Finally, perspectives for further developments and coupling of the two systems are presented.
Carmen Pardini - One of the best experts on this subject based on the ideXlab platform.
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Collision Risk Mitigation in Geostationary Orbit
Space Debris, 2000Co-Authors: L. Anselmo, Carmen PardiniAbstract:The short- and long-term effects of spacecraft explosions, as a function of the end-of-life re-Orbit altitude above the Geostationary Orbit (GEO), were analyzed in terms of their additional contribution to the debris flux in the GEO ring. The simulated debris clouds were propagated for 72 yrs, taking into account all the relevant Orbital perturbations.
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Collision Risk Mitigation in Geostationary Orbit
Space Debris, 2000Co-Authors: L. Anselmo, Carmen PardiniAbstract:The short- and long-term effects of spacecraft explosions, as a function of the end-of-life re-Orbit altitude above the Geostationary Orbit (GEO), were analyzed in terms of their additional contribution to the debris flux in the GEO ring. The simulated debris clouds were propagated for 72 yrs, taking into account all the relevant Orbital perturbations. The results obtained show that 6–7 additional explosions in GEO would be sufficient, in the long term, to double the current collision risk with sizable objects in GEO. Unfortunately, even if spacecraft were to re-Orbit between 300 and 500 km above GEO, this would not significantly improve the situation. In fact, an altitude increase of at least 2000 km would have to be adopted to reduce by one order of magnitude the long-term risk of collision among Geostationary satellites and explosion fragments. The optimal debris mitigation strategy should be a compromise between the reliability and effectiveness of spacecraft end-of-life passivation, the re-Orbit altitude and the acceptable debris background in the GEO ring. However, for as long as the re-Orbit altitudes currently used are less than 500 km above GEO, new spacecraft explosions must be avoided in order to preserve the Geostationary environment over the long term.
M Temerin - One of the best experts on this subject based on the ideXlab platform.
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quantitative prediction of radiation belt electrons at Geostationary Orbit based on solar wind measurements
Geophysical Research Letters, 2001Co-Authors: X Li, M Temerin, D N Baker, G D Reeves, D E LarsonAbstract:Solar wind measurements are used to predict the MeV electron radiation belt flux at the position of Geostationary Orbit. Using a model based on the standard radial diffusion equation, a prediction efficiency of 0.81 and a linear correlation of 0.90 were achieved for the years 1995–1996 for the logarithm of average daily flux. Model parameters based on the years 1995-1996 gave a prediction efficiency and a linear correlation for the years 1995–1999 of 0.59 and 0.80, respectively. The radial diffusion equation is solved after making the diffusion coefficient a function of the solar wind velocity and interplanetary magnetic field. The solar wind velocity is the most important parameter governing relativistic electron fluxes at Geostationary Orbit. The model also provides a physical explanation to several long standing mysteries of the variation of the MeV electrons.