Research into coronal mass ejections by the method of two-position radio sounding method

The two-posision radio sounding of the solar wind by Galileo and Cassini space vehicles was first realized. These space vehicles were following the Sun from east to west from 12 to 24 May 2000. Their signals were sounding regions spaced in radial directions to several millions of kilometers. A stable correlation was revealed between fluctuation effects registered in spatially spaced radio-sounding paths of disturbed plasma structures of coronal mass ejection (CME) type. A correlation was also found between radio effects and data on the solar wind density near the Earth orbit. It is shown that the two-position radio-sounding method with data on solar radiation in the X-ray and optic ranges and with results of local plasma measurements enables information to be gained about structure and velocity of CME travel from the photosphere to the Earth orbit. In the most energetic event recorded on 13 May 2000 the CME velocity at the heliocentric distances of about 15Ro (Ro is the Sun's radius) ran to 1200 km/s. At (15+25)R0, the velocity was about 1300 km/s. At distances more than 25Ro, the disturbance slowed down with decreasing velocity from 1300 km/s to 450 km/s near the Earth's orbit.