How much solar sail and vane surface area would be needed to replace the boosts needed to keep the ISS in orbit? Could this be done at a higher orbit minimizing atmospheric drag?
What is the closest to Earth you can expect lift from a solar sail?
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2$\begingroup$ Try to calculate the necessary size. How much time of an orbit the sails would deliver a useful force to the right direction for lifting the orbit? Would the force of the solar sails be substantialy bigger than the increased drag caused by the sails? $\endgroup$– UweCommented Oct 14, 2018 at 18:44
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1$\begingroup$ @Uwe thanks. I believe that with certain angles in the sail shadows overlapping canceling radiation pressure a certain angles in relation to the sun and the right orbit that a modified solar sails can be made to always have orbital stability? A mast would be needed. $\endgroup$– MuzeCommented Oct 14, 2018 at 18:52
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Ignoring the ISS, the question is simply whether light pressure on the sail can counteract the drag on the sail from atmosphere. Light pressure near Earth is about $10 \mu Pa$ (with optimum geometry and no eclipse). So the question is what is the drag force per square meter of sail. We know that the ISS experiences about 0.2N of drag, and its area is dominated by the solar panels at around $2500 m^2$ suggesting a drag pressure in the vicinity of $80 \mu Pa$ at that altitude. So any sail will add more drag than boost.
answered Oct 14, 2018 at 20:41
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6$\begingroup$ Interestingly this basically says that solar sails are useless in general (at least to lift your orbit) until you are some way above the ISS altitude. $\endgroup$ Commented Oct 15, 2018 at 8:11
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$\begingroup$ What if it boosted to a higher orbit then which to solar sail would be deployed? $\endgroup$– MuzeCommented Oct 15, 2018 at 23:21
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1$\begingroup$ @muze see one of the 4 existing questions about why thats not a useful idea. A LEO space station is easy access- go much further than that and you need much more deltaV to rendevouz. $\endgroup$ Commented Oct 15, 2018 at 23:47
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$\begingroup$ @MagicOctopusUrn but I am not convened that a hybrid diamagnetic solar sail couldn't do where a solar sail alone could. $\endgroup$– MuzeCommented Oct 16, 2018 at 0:00