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Removing orbital debris with lasers 总被引:2,自引:0,他引:2
Claude R. Phipps Kevin L. Baker Stephen B. Libby Duane A. Liedahl Scot S. Olivier Lyn D. Pleasance Alexander Rubenchik James E. Trebes E. Victor George Bogdan Marcovici James P. Reilly Michael T. Valley 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
Orbital debris in low Earth orbit (LEO) are now sufficiently dense that the use of LEO space is threatened by runaway collision cascading. A problem predicted more than thirty years ago, the threat from debris larger than about 1 cm demands serious attention. A promising proposed solution uses a high power pulsed laser system on the Earth to make plasma jets on the objects, slowing them slightly, and causing them to re-enter and burn up in the atmosphere. In this paper, we reassess this approach in light of recent advances in low-cost, light-weight modular design for large mirrors, calculations of laser-induced orbit changes and in design of repetitive, multi-kilojoules lasers, that build on inertial fusion research. These advances now suggest that laser orbital debris removal (LODR) is the most cost-effective way to mitigate the debris problem. No other solutions have been proposed that address the whole problem of large and small debris. A LODR system will have multiple uses beyond debris removal. International cooperation will be essential for building and operating such a system. 相似文献
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Nicholas W. Watkins Daniel Credgington Bogdan Hnat Sandra C. Chapman Mervyn P. Freeman John Greenhough 《Space Science Reviews》2005,121(1-4):271-284
Mandelbrot introduced the concept of fractals to describe the non-Euclidean shape of many aspects of the natural world. In
the time series context, he proposed the use of fractional Brownian motion (fBm) to model non-negligible temporal persistence,
the ‘Joseph Effect’; and Lévy flights to quantify large discontinuities, the ‘Noah Effect’. In space physics, both effects
are manifested in the intermittency and long-range correlation which are by now well-established features of geomagnetic indices
and their solar wind drivers. In order to capture and quantify the Noah and Joseph effects in one compact model, we propose
the application of the ‘bridging’ fractional Lévy motion (fLm) to space physics. We perform an initial evaluation of some
previous scaling results in this paradigm, and show how fLm can model the previously observed exponents. We suggest some new
directions for the future. 相似文献
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