*Sigh*
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For those who are interested http://www.ugcs.caltech.edu/~diedrich/solarsails . This is Caltech's Solar Sail website. It has TONS of great data.
The site has some detailed explanations of what solar sails are, how they work, and how they can be used to let a vehicle approach the star.
#1 Solar sails do not harness the solar wind:
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Many people assume that because here on Earth they feel wind but not sunlight, that solar sails must be pushed by the solar wind. However, there is a very big difference between space and Earth. Earth is wrapped in a thick layer of gas that is felt as wind whenever it moves. In space, there is no air to move around and cause strong winds like we feel on Earth. The solar wind is an extremely tenuous flow of particles ejected by the sun which exerts very little force on anything it hits. The reason people worry about the solar wind is because many of the particles have an electric charge that can hurt people and electronics, or can push a magnetic sail.
#2 They approach a star not by tacking, but by narrowing an orbit (a very slow process).
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Solar sails are more complex. The force produced by sunlight on a solar sail is the addition of the forces from the incoming sunlight and the reflected sunlight. This force always points away from the sun, and is at an angle that is close to a right angle to the surface of the sail. If this force is angled back along the solar sail's path, the spacecraft's orbit will start to shrink, bringing it closer to the sun. If the force is angled foreward along the spacecraft's path, the orbit will grow and the solar sail will head farther from the sun.
This is the general idea behind "tacking into the sun" for solar sails. In real practice, the behavior of a solar sail is more complicated because sunlight pushes not only along the spacecraft's orbit, but also straight out from the sun. These effects are beyond the scope of this document, however.
You can find all kinds of neat ideas, including several different designs of potential solar sails, and some fun facilities to make use of them. For example, NASA was considering using a massive ground-based laser (5-million megawatt) on continual fire to propel a solar-sailed raft to Alpha Centauri, until the ion and plasma pulse rockets turned out to be both cheaper and faster.
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