Researchers at the Institute of Space and Astronautical Science (ISAS) and the University of Tokyo studied solar wind flowing a long distance from the Sun's vicinity, whose distance is about 20 times the radius of the Sun, and found that the wind drastically accelerated at around a location that is five times the radius away from the Sun. They also clarified that the acceleration of solar wind in such a faraway place was related to heating cause by an energy source of waves transmitting through solar wind.

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