|MadSci Network: Astronomy|
The maximum speed of the solar particle flow is approximately 800 kilometers per second, and that occurs very near the Sun. Moreover, this particle flow, or solar wind, attenuates considerably over the billions of kilometers required to travel outside the Sun's "region of influence" and into interstellar space. Given the low density of the solar wind, it is not envisaged that the acceleration to appropriate interstellar speeds would be possible with such a system.
The idea of lasers in near solar orbit focussing light onto a collecting plate at the rear of a spacecraft is thought to be much more promising (see work by Robert Forward). Speeds of perhaps 1/3 the speed of light might be reached using extremely thin films as a "solar sail" for collection of this laser radiation; "tacking" these solar sails at the destination star would allow some deceleration from the star's light. Lasers could send a collimated beam carrying more energy much further out away from the Sun than the solar wind.
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