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Finnish Electric Solar Sail Nears Implementation
eldavojohn writes "A recent meeting held by the Finnish Meteorological Institute has resulted in plans to build an electric solar sail that will circle the Earth, gaining speed to test its acceleration. The purpose? 'A flight out of the solar system to measure the gas, dust, plasma and magnetic field in the undisturbed interstellar space would perhaps be the "flagship" thing to do,' said Pekka Janhunen, a researcher developing the sail at the FMI. The details and papers of this project (over two years in the making) are also available. I certainly hope it will show more success than the launch of the similar U.S.-Russian venture and its subsequent complete failure."
It does use the momentum of the solar wind like any other solar sail; the difference to the other attempts is that this one uses an electric field around wires rather than a big physical surface to "catch" the solar wind particles. It'll be less efficient per surface area than a membrane sail, but allows the surface area to be astonishingly large relative to the mass of the spacecraft (compare the weight of a mile-long wire to a square mile of plastic sail) so it may still have a huge advantage.
I agree with AC.
The tendrils are not for power generation.
The craft generates electricity using the solar panels which powers an electron gun. The electron gun gets rid of electrons allowing the entire spacecraft (solar sail tendrils included) to become positively charged and then catch the solar wind for propulsion.
The electron gun can also provide a tiny amount of thrust. A very tiny amount of thrust.
You better go call up the scientists! I bet they didn't think about this!