This is actually the second attempt that the Planetary Society has made to launch an solar sail experiment. They tried earlier in 2005, but the Volna launch failed and the payload ended up in the Barents Sea. The current LightSail-1 payload is a continuation of the NASA "
NanoSail" project, which was cut from the NASA In-Space Propulsion research program after the loss of the first flight experiment when the SpaceX Falcon-1 launch failed. At the time that it was cut, the Planetary Society, which has had a long-term interest in alternative propulsion technologies, offered to continue the project with private funding.
-dave
/edit/ (and Dave posted a lot of this already while I was looking for the NanoSail link)
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