The IKAROS solar sail which was deployed by Japan Aerospace Exploration Agency (JAXA) in June 2011 has flew by Venus on December 8, marking the success of the world’s first demonstration of a solar power sail in space.
As its name indicates (Interplanetary Kite-craft Accelerated by Radiation Of the Sun), IKAROS is a kite-like spacecraft which is powered by radiation pressure in interplanetary space – a method which will be useful for future space exploration within the solar system in many ways, and with possibility of doing things at much lower cost.