I'm not flamming you,
but I dissagree on two points:
> point out that although simliar to light sails, solar
> sails also use the solar wind, ions and also sub-atomic
> particles being spewed outward from the sun. Only
> upcoming experimentation will determine how much thrust
> is provided by the solar wind
actually, we can measure that right from earth....
we know how much radiation is coming from the sun (many satelites study that very thing) and therefore we can calulate the force it would exert on this sail of known dimensions.
> The problem with using gravity to return is you still
> need some way to decelerate from solar orbital velocity.
gravity will decelerate us from our velocity as long as we don't reach solar escape velocity (I don't know what this is, but it's the same principle as launching things into orbit.... if you don't go fast enough you'll come right back down). the son's gravity reaches out much furthur than pluto (note: comets exist out past pluto but aren't going fast enough to break solar escape velocity so they keep coming back). so it would still be able to slow us down.
> Otherwise, you won't fall toward the sun you will simply > orbit around it.
not really likely, more likely we would fall back INTO the sun....
last note:
the fastest man made object happens to be a PIONEER satelite which was launched in the 70's.
it achived solar escape velocity by executing a lunar fling on one of jupiter's moons then a planetary fling from jupiter, and finaly another fling using saturn this time.
it's going out there into the cold, never to return..... in the 90's it sent back (it's last transmission) a picture of the entire solar system back to earth....
go here for more information:
<A HREF="http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome.html" target="_new">http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome.html</A>