# Re: Laser Aperture Size

```At 08:50 PM 3/11/96 -0500, you wrote:

>Not if your still at near light speed.  Ignoring that, could you generate
>that much power?  How much would it take?  And how do you decel to a stop
>inside the star system?
>
If you can manage to accelerate to near light speed in 100+ days, then you
should be able to do a 180 in 300+ days. As for power, probably too much. It
doesn't matter what the propulsion method is, the amount of power necessary
to accelerate a given mass to a given velocity is constant, the only thing
that changes is how efficiently we can use that power. (Besides Forward et
al never planned on doing a turn at near light speed, they were talking

The Lorentz idea would probably consume 3 to 4 times as much power as a
straight decel, its only advantage was that it removed the need for any
retro mirrors, reflectors, advance robot missions, etc. Decel was by light
sail on the same beam you came out on, but since you now have a vector back
the way you came, it will now decelerate you instead of acclerate you.

Of course, all this presupposes that a Sol based beam can even reach that
far. Perhaps you could use the star's light to decelerate partially for a
relatively low speed fly by then use Lorentz force to bend your vector back
around to the star again and use the star to decelerate some more?

:-)

Lee
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+  Weave a circle 'round him thrice, and close your eyes with holy dread...   +
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