Abstract
The two-position radio sounding of the solar wind by the Galileo and Cassini spacecraft has been first performed. These spacecraft followed the Sun from east to west from May 12 to 24, 2000 and sounded the regions spaced in radial directions by several millions of kilometers. Stable correlation has been revealed between fluctuation effects detected in spatially spaced radio-sounding paths of disturbed plasma structures of the coronal mass ejection (CME) type. The radio effects have been found to correlate also with the data on the solar wind density near the Earth orbit. It has been shown that the two-position radio-sounding method together with the data on solar radiation in the X-ray and optic ranges and with the results of local plasma measurements provides information on the structure and velocity of the propagation of CMEs from the photosphere to the Earth orbit. In the most powerful event recorded on May 13, 2000, the CME velocity at the heliocentric distances of about 15R ⊙ (R ⊙ is the solar radius) reached 1200 km/s. At (15–25) R ⊙, the velocity was about 1300 km/s. At distances larger than 25R ⊙, disturbance was decelerated from 1300 to 450 km/s near the Earth orbit.
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Original Russian Text © A.I. Efimov, N.A. Armand, L.A. Lukanina, L.N. Samoznaev, I.V. Chashei, M.K. Bird, 2008, published in Solnechno-Zemnaya Fizika, 2008, Vol. 12, No. 1, pp. 114–118.
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Efimov, A.I., Armand, N.A., Lukanina, L.A. et al. Investigation of coronal mass ejections by the two-position radio sounding method. Geomagn. Aeron. 49, 1165–1169 (2009). https://doi.org/10.1134/S0016793209080258
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DOI: https://doi.org/10.1134/S0016793209080258