# Re: For Consideration

```To Kevin:

>> As long as the fuel is prelaunced there is no problem, but you were
>> suggesting to use the fuel as shielding. If you planned using that fuel for
>> deceleration, it could not work because there isn't an engine that can stop
>> it.
>
>only true for internally powered engines, an externally powered MARS
>design, would be able to carry enough reaction Mass (I hope) to overcome
>both the photonic thrust, and slow the ship at 1 G (10 m/s^2)

Yes, I forgot that possibility.

>By accelerating the Reaction Mass (RM) to near light speed, we could
>increase it's momentum endlessly (by approaching the speed of light ever
>closer) thus allowing less RM to escape out the back of the ship. by
>using the maser antenna as a "sail", and retro-reflecting most of the
>energy, we could accelerate away from earth at a nice 1 G (and since the
>exhaust speed would be C (photons) the RM would be zero.  at the
>turn-around point, instead of reflecting the maser beam, we would convert
>it to electricity, and accelerate RM in the direction of TC.  But there
>wont be enough energy to overcome the momentum imparted by the photons
>absorbed, to raise the exhaust speed up to .9996 C.  Thus our mass costs
>will go up.  instead of accelerating a small amount of RM to Near-light
>speed, we will have to accelerate a larger amount to some lower speed
>(perhaps .75 or .8 C)  I would love to tell everyone that I had solved
>this little mystery, but alas, I have been very busy with school-work.

Yes, it will work, I calculated it. To say it in words you should accept the
fact that mass have a better momentum/energy ratio than photons. So this
means if you have an amount of energy and want to get the most momentum out
of it, then you should accelerate mass and not shine photons. (Of course
this means that you have that mass, which as we all know is not favourable
in a starship)

>on anti-biotics, Kelly is right.  all my Bio-Chem Books show that
>Anti-biotics attacks certain specific Key reactions that all life must
>use.  For example, Sulfa drugs attack the Flavin pathway.  Thus unless
>the bugs are supplied with the component, they cannot survive (unless
>they have a mutant enzyme which can distinguish between the proper flavin
>precursor and the sulfa drug.  This is what I meant by the evolutionary
>age of the life being important.

So does this mean that we can kill alien-life with anti-biotics as long as
their development is not far beyond ours?

Timothy

```