Re: superhero space navigation

Leonard Erickson skreiv:
> On Tue, 08 Apr 2008 19:14:08 +0200, Eivind Kjorstad
> <eivindorama@[EMAIL PROTECTED]
> wrote:

>> Constant _acceleration_ like "1G indefinitely" drives are already deep 
>> black magic and unphysical if powered by onboard matter pretty quickly.

>> (even total mass-energy conversion can't do it for VERY long)
> 
> Long enough to be rather surprising when you get right down to it. 
> I believe the late Dr. Forward did a rough design for an antimatter
> powered vessel that could do a constant accel to Alpha Centauri. 
> It wasn't *high* accel, but...

It certainly wasn't "1G indefinitely". If you're satisfied with 
arbitrarily low acceleration, then it's not hard to make a drive that 
can do (near) constant acceleration for a very long time.

Just hook up one of them things that create electricity from the heat of 
some radioactive substance with a significant half-life, and connect the 
electricity to a flashlight of some sort pointing backwards.

Voila ! Constant acceleration for decades, centuries if you do the 
mechanical design well-enough to hold up.

That's not going to give you anything in the neighbourhood of 1G though.