The electromagnetic radiation carried by solar wind exerts pressure on surfaces that absorb or reflect it. Though small, this force can be harnessed and used as a form of space propulsion requiring no fuel. Solar sails are lightweight, highly reflective devices that harness this force and, when attached to spacecrafts, may be used to modify their orbits, perform fine trajectory corrections, and even drive interplanetary flights. Has a working solar sail ever been successfully tested? Discuss
Source: The Free Dictionary