Re: Slow Re-entry

Bryan Derksen wrote:

> On Sun, 07 Aug 2005 19:51:58 -0500, Mad Bad Rabbit
> <madbadrabbit@xxxxxxxxx> wrote:
>
>>"arne97" <gahada2001@xxxxxxxxx> wrote:
>>
>>> What with broken tiles and what-not, isn't there a better way to
>>> get a ship down those last 200 miles than turning it into a meteorite ?
>>
>>Yes, a space-elevator ; but we need several thousand kilometers
>>of superstrong cable that we're not able to manufacture just yet.
>
> Actually, I don't think a space elevator would be too useful to
> something that's in a 200 mile orbit. The elevator's not moving at
> orbital velocity, so to dock with it at the 200 mile mark you'd need
> to kill your velocity with respect to the ground. That's the problem
> that we're trying to deal with anyway.

The point is that we don't need to be in orbit at 200 miles. You go up the
elevator, do the job, and head back down. Forget the ship.

> For something in geosynchronous orbit or close to it, yes, a space
> elevator is ideal.

Since it's easier on the elevator to get to geosynchronous orbit than to
LEO, that's what we do. We can discuss matching velocities at
geosynchronous orbit and higher for interplanetary craft or Earth-Moon
craft, whenever we get engines capable of several km/sec delta-V using less
than their own mass of fuel and reaction mass.

> For lower orbits a rotating tether might work okay.

Crawling out to the end of a tether and letting go at the right moment to go
into orbit sounds feasible to me. Catching a tether from orbit sounds like
a nightmare.
.

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