Yahoo group Return to the moon

From:  "vincecate" <vince@o...>
Date:  Thu Jan 15, 2004  8:53 pm
Subject:  Rotating Space Tethers

If you want to operate a moon base, having some space tethers
can greatly reduce your costs.

Rotating space tethers can be built today, unlike a space elevator
which needs materials that we may not have for 50 years or more.
They do not need anything stronger than Spectra-2000, which is used
for fishing line.

A rotating space tether is long (like maybe 500 km long) with a weight
at one end. It is rotating around its center of mass, which is close
to the weighted end. The whole thing is in orbit around the Earth. It
is spinning fast, like maybe 2.5 km/sec at the tip. The tip is going
backwards relative to the orbital speed when it is down and forwards
when it is up. So when it is down you can transfer a payload from a
suborbital rocket to the tether, even though it is not going at
orbital speed.

The reusable 1st stage of the SpaceX Falcon-1 could lift a payload
high enough and fast enough for a practical tether to catch it.
We call this Single Stage To Tether (SSTT). This could make for very
cheap access to space.

You can also have a tether around the moon to lower and lift payloads
there.

I have a Java applet that you can use to simulate space tethers at my
site so you can see how they work:

http://spacetethers.com/

I really think this is the best way to get into space with current
materials.

-- Vince