Finnish space boffins have been awarded €1.7m and placed in charge on an international effort to build the fastest thing ever made by the human race – namely a spacecraft propelled by the pressure of sunlight striking an enormous electrical field.
The "electric solar wind sail" is not your common or garden solar sail, familiar to many Reg readers, in which the solar wind strikes something physical – a fabric or film, probably extremely thin and light – and the resulting minuscule pressure exerted over a large area very gradually accelerates the sail and its attached spacecraft. No, the Finns are having none of that – the necessary vast acreage of sail fabric required to achieve even a feeble push would be too much bother, they feel.
Rather, in the electric version, the ship deploys instead 50-100 20km-long, extremely fine (25 micron thick) cables. These are arranged in a circle and the whole thing spins, keeping the wires stretched out in a huge, 40km-across disc like the spokes of a wheel. A positive potential of, say, 20,000 volts is put on the wires (requiring only a few hundred watts of power, as almost no current is actually flowing).
For more: Electric forcefield space sailing-ship tech gets EU funding • The Register
No comments:
Post a Comment