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Notes:
Before we look at the technology, let us look at the promise. Winglee has suggested that a 30km diameter mini-magnetosphere is possible with current technology. A rough estimate is that the satellite weighs 100kg, the gas plasma supply weighs 100kg and the added dust to achieve 2% opacity weights 100kg. That results in a net force of 91 nPascals, which on a 30km disk give 64 newtons of thrust. Dividing by the mass, we obtain 0.21 m/s2 of acceleration, or 2% of the acceleration of gravity. That is an enormous number for a solar sail. Using that constant acceleration simplification again, we obtain 36 days to Mars, 72 days to Jupiter and only 7.4 months to Pluto. (Actually, for a magnetic plasma sail expands as it leaves the Sun, producing a nearly constant thrust during its early mission profile, providing some justification for our simplification.) This achieves more than we desired for our goal, and we haven’t even pushed the opacity of dusty plasmas to its limit. But is it practical or even possible to make a dusty plasma sail?