As I recall the Sunshield episode of Discovery Project Earth
considered a coil gun for launching lenses to deflect light away from
Earth. The project called for a coil gun over a mile long to launch
800,000 lenses .04 oz / 1 gram each every five minutes. Such a coil
gun was estimated to take 30 years to develop if research was geared
up substantially from current levels *now*.

So how does the induced force of lauching say, 10, let alone the 70
metric tons the StarTram proposal calls for at 2.5 gs over 1250 km
compare to the force required to launch .8 metric tons over probably
something like 2 km at much higher gs? The paper I downloaded a long
time ago says that the "acceleration drive power" is 28 GW.

Let's see, the mass launched under StarTram is 87.5 times greater, but
the force is spread out over greater time and distance. The distance
is is probably something like 625 times greater. My guess is that
StarTram is probably more doable.

I have two papers I downloaded back when you could get them for free.
Do I dare in this age of perpetual copyreich to upload them to the
files section (assuming that feature is even on)? I suspect that some
changes/corrections have been made since then.

I'd hate to wait 30 (or even 10) years for solutions to Global Warming
and fossil fuel dependence. I'd rather have Space-based solar power
than a Sunshield. Even at this point, we may already need both I
suppose.

Even if you can produce solar cells at 10 cents per watt, how long
will they last without a glass or plastic cover to protect them from
the elements? Then what are your costs? Perhaps an aerostat version
of Cool Earth Balloons (www.coolearthsolar.com) is a posibility. If
we need to get our power from space-based solar power and the only way
to do it now is to use the "nuclear option(tm)" I say go for it.

The Case For Orion by Wayne Smith
http://www.spacedaily.com/news/nuclearspace-03h.html

Note:"nuclear option" is a registered trademark of Rupert Murdoch's
Propaganda Corp.

----- Original Message -----
From: Andreas
To: space-elevator@yahoogroups.com
Sent: Tuesday, June 02, 2009 2:54 PM
Subject: [space-elevator] Re: Star Tram






Check out this cool paper:

http://science.ksc.nasa.gov/shuttle/nexgen/Nexgen_Downloads/Spaceport_Visioning_\
Final_Report.pdf

There used to be a company named Star Tram Inc., and a web-site with
cool pictures less than a year ago. We may have brought it up oon this
forum once or twice, I don't remember. Now, I can't find a trace of it
except for the patent and the above document (Ask me for a copy if
those disappear, too .. Wait, I hear someone knocking down my door :-)

Andreas