Re: Guerilla Internet Service Providers (fwd)

[jim bell <jimbell@pacifier.com>]

At 01:47 PM 1/2/96 -0600, you wrote:
>
>Forwarded message:
>
>> Date: Tue, 2 Jan 1996 18:43:31 +0000 (GMT)
>> From: "Mark Grant, M.A. (Oxon)" <mark@unicorn.com>
>> Subject: Re: Guerilla Internet Service Providers
>> 
>> About ten years ago a group I was involved with were thinking about
>> putting something into space as a publicity stunt. One company we talked
>> to claimed they could put 1 kg into orbit on one of their sounding rockets
>> for about $ 30,000 (that's a 1 kg satellite, not $ 30,000 per kg). How
>> small can you build a "data haven" satellite ? 
>> 
>> Looking a few years into the future, you could probably stick a
>> stripped-down Linux laptop with solar cells and a stripped-down satellite
>> telephone as a Net link on top of a slightly larger rocket and charge for
>> on-orbit storage using ecash... Using remailers it should be pretty-much
>> untraceable. 
>> 
>
>Actualy, both the Pacific Coast Rocketry group and the Experimental
>Spacecraft Association are working on putting the first amateur payload in
>LEO. ESA wants to put a telescope with real-time downlink up as their
>payload. PCR wants to put some kind of transponder up.
>
>Under current technology a group of about 30 dedicated amateurs (with
>suitable skills) could put a 25kg payload in orbit for under 1/4 million.
>It would consist of surplus and amateur built equipment.
>
>Tripolli puts out a magazine called High Performance Rocketry which you may
>be able to find at your local newstand (in Austin you get it at the Central
>Market Bookstop). It usually carries at least a couple of adds for material
>that PCR and a couple of smaller groups are putting out to help fund their
>project. I would say it will be less than 3 years before this dream occurs
>unless the DOT (the people who regulate all space shots now) decides not to
>give them a permit.

As I understand the physics, the whole process could be made FAR FAR FAR
more efficient if the rocket was boosted to about 40000 feet with a subsonic
airplane, a' la' X-15 and such.  It's above 75% of the earth's atmosphere
(dramatically reduced drag), is already going 600 mph in the correct
direction, and is 8 miles closer to the  ultimate goal 250 miles up).  This
might not sound like much of an advantage, but if you've ever worked out the
mathematics of the Saturn V (or space shuttle, etc), the VAST majority of
the fuel was used up in the first 20,000 feet, maybe even the first 5000
feet.  It would be even better if the first stage could be an air-breathing
supersonic ramjet, but that's not my field of expertise.

In addition, the existence of relatively low-cost GPS receivers would make
achieving an accurate orbit vastly cheaper than with the inertial guidance
systems historically used.  Sure, cheap accelerometers are being sold by
Analog Devices and Murata Erie sells cheap vibrational gyros (not to mention
fiber gyros) but it would be hard to beat the accuracy you could get with GPS.