--- Russell McMahon <apptech@paradise.net.nz> wrote:

> > I left a wrong impression!  They didn't foolishly imply you can fly
> a 
> > balloon to the moon ala' Jules Verne, The idea was to get as high
> as 
> > possible with a balloon, then use a smaller rocket motor to move it
> up 
> > slowly, over a period of days, not minutes, beyond the atmosphere.
> 
> They are, alas, totally dreaming. Or they have conveyed the wrong 
> impression. Anything hanging above the surface of the earth MUSt be
> subject 
> to a force that balances gravity. Gvrity is essentially 1g at LEO and
> is 
> still substantial at geosynchronous level. The balancing force may be
> 
> centrifugal force due to velocity tangentially to the gravity vector
> or 
> thrust from by other means against gravity. As the centrifugal force 
> increases with velocity squared it isn't very useful incombatting
> gravity at 
> low tangential velocities. For a balloon this leaves "thrust from
> some other 
> means". If a rocket is to be used it will have to support the vast
> majority 
> of the vehicles mass (including its own weight and that of its fuel)
> against 
> gravity. This dog don't hunt - or, at least, not for more than well
> under an 
> hour. Even going to air breathing engines will give you an extension
> in Isp 
> of 5 to 10 times. And there won't be any useful air in this
> environment.
> 
> Summary: A balloon CANNOT be used to achieve orbital altitudes for
> long 
> periods.
> 
> > At that point the balloon part is useless, and could be pumped down
> and 
> > stored, but your platform has gotten a really cheap ride to the
> edge of 
> > the flyable atmosphere.
> 
> This is true - but the "days not minutes" scenario doesn't work.
> 
> I wish the above WAS possible, but it's not. I suspect that they have
> failed 
> to properly convey some important aspects of their system. Failing
> that they 
> are charlatans.
> 
> Got a web address for them?
> 
> 
> 
>         Russell
> 

right, how do you anchor that sucker out there? a balloon?  then what's
 the anchor beyond the balloon?  rockets?  The anchors have to
withstand the lift what ever you're elevating.  So then isn't the
'space rocket' in effect lifting the mass off of the ground?


 



		
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