Astrophysics and Space Sciences Transactions www.astrophys-space-sci-trans.net 1810-6528 1810-6536 5 1 2009 10.5194/astra-5-35-2009 http://www.astrophys-space-sci-trans.net/5/35/2009/ http://www.astrophys-space-sci-trans.net/5/35/2009/astra-5-35-2009.html http://www.astrophys-space-sci-trans.net/5/35/2009/astra-5-35-2009.pdf 35 38 2009-08-06 On expansion of magnetic clouds in the solar wind M. Vandas vandas@ig.cas.cz A. Geranios E. Romashets Astronomical Institute, Academy of Sciences of the Czech Republic, 14131 Praha 4, Czech Republic Physics Department, University of Athens, Panepistimioupoli-Kouponia, Athens 15771, Greece Prairie View A& M University, Mail Stop 2250, PO Box 519, Prairie View TX 77446, USA Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation of Russian Academy of Sciences, Troitsk, 142190, Russia Magnetic clouds are supposed to be large interplanetary flux ropes propagating away from the Sun. 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