At 06:48 PM 10/15/2004, David Minkler wrote:

>Which mechanism?
>
>1.  Solar sail, standard configuration.
>2.  Solar sail, released and used in reverse
>3.  Using the sail as reaction mass

#2. IIRC they were illuminating it with a kick ass laser.

>Obviously, the effectiveness of 2 vs.. 3 depends upon the mass to area 
>ratio of the sail (and its reflectivity).  There may be a sweet spot (or 
>curve).  A ball of tungsten would probably favor 3.  A sail with a mass to 
>area ratio of zero would accelerate away from the sun so fast you'd get no 
>benefit from the reflection.

Careful, light still moves at C, so the only thing that happens is the 
wavelength redshifts downward, twice the shift caused by the recession speed.


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