NASA's solar sail (Picture I) Kimmo Huosionmaa In this text, I would think about fictional space trip to Alpha Centauri by using solar sails, what are boosted with laser or microwave beams. The use of lasers with solar sails would give very much improvements to that system. The problems with laser-systems are that the material of the targeted spacecraft would be heated in extreme temperature, but when we are thinking about the use of lasers as the improve the thrust of that very large sail, we must think this problem practically. Big size of solar sails would allow that the heat of the laser rays would circulate in the larger area, and that would help to decrease the heat, what powerful lasers would send to the target. Those lasers, what would be used in that kind of program, might be kilometers long, and they might be stationed near the Earth. Making those kilometers long free-electron lasers or powerful masers is a quite simple thing. There must send many small ...