This article claims that spin rate is directly proportional to radio frequency emitted by the dust: http://www.economist.com/node/863276 http://www.economist.c

This article claims that spin rate is directly proportional to radio frequency emitted by the dust: http://www.economist.com/node/863276 http://www.economist.com/node/863276 > What is impressive is the rate at which the particles spin. It has to be equal to the frequency of the radio wave that is emitted, so Dr Finkbeiner's observations imply that many of the dust particles are rotating at ten billion revolutions per second.