Re: starship-design: Back from the wed

[jimaclem@juno.com]

On Thu, 24 Jul 1997 11:35:21 -0700 wharton@physics.ucla.edu (Ken Wharton)
writes:
>

>simplest, but we have to give a lot of photons to each proton to get 
>the 
>energy/mass ratio to come out right.  Each proton will need 230GeV 
>imparted to it, and it seems unlikely we can give a proton that much 
>energy from a microwave beam without an "active" engine, where the 
>energy distribution is manipulated by an accelerating structure.  For 
>mm-sized microwaves, this is 10^15 photons per proton!  Perhaps 
>starting 
>off with a lower proton energy would be okay; if you transfer all the 
>energy, the slower the protons the more you slow down, paradoxically 
>enough.  The problem with slow protons, though, is that you need a LOT 
>
>of them to do the job of a few fast ones.  If you shoot off too much 
>mass too slow you'll run out of sail material before you can slow down 
>
>enough...
>
>Run with this, someone...
>
>Ken Wharton

Okay, I'll run with it.  How about using a small supply of antimatter (
not sure yet how much ) and using this to heat the reaction mass to high
enough energies to make this efficient.  For that matter, why not use the
tanker ideas to launch reaction mass to a ship, while it only carries the
necessary antimatter.

Jim Clem
>
>
>"No brakes?  Well, no point in steering now"
>(Bob MacKenzie, Strange Brew)
>