re: Fuel Chat

At 02:55 PM 11/27/98 -0500, you wrote:
[snip]
>
>What the heck is a 'photon' drive?  How does this produce thrust?

A photon drive basically uses a directed beam of light (or invisible
electromagnetic radiation). The momentum of the photons (h*f/c where
h=planck's constant, f=frequency of the light and c=speed of light)
is transferred to the light source. Normally, the light is emitted 
in all directions, producing a net result of zero, hence the need for 
reflectors to direct the beam. Another example of a space drive that 
uses the same principle is the solar sail, but that relies on the 
solar wind instead of a light source integrated into the spaceship.
This limits its application to non-military uses where arbitrary 
maneouvering is the exception rather than the rule.

An interesting consequence of this principle is that you can 
calculate (although not measure) the amount that your car slows down 
when you turn on your headlights :)

>Curious
>
>Sid Jones
>
Hopefully this makes sense!

       Tony Christney
       acc@questercorp.com

  "If the end user has to worry about how the program was 
   written then there is something wrong with that program"
				  -Bjarne Stroustrup