Archived posting to the Leica Users Group, 2007/02/25

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Subject: [Leica] Re: GPS
From: marcsmall at comcast.net (Marc James Small)
Date: Sun Feb 25 12:23:48 2007
References: <200702250609.l1P67qAK011689@server1.waverley.reid.org> <C9E317F5-6BE2-4DA6-AAB4-0959F45807F5@optonline.net> <200702251912.l1PJCKvV074422@server1.waverley.reid.org> <4cfa589b0702251132w510d7283o7737e2eb2a335e22@mail.gmail.com>

At 02:32 PM 2/25/2007, Adam Bridge wrote:
 >The GPS constellation orbits about 12,000 miles above the surface, NOT
 >in low Earth orbit. The satellite the Chinese hit was about 500 miles
 >up. This is useful for hitting spy satellites but getting up to 12,000
 >miles is a different kettle of fish and MUCH  more difficult. There's
 >a reason they are that high.
 >
 >Add in the ESA constellation at 14,000 miles or so and you have a
 >difficult problem. Vehicles built to reach either constellation are
 >NOT aircraft launchable and I think they are sufficiently large as to
 >be not portable-launch either.
 >
 >Since shooting at either constellation would be a serious act of war
 >in and of itself a ballistic response to the launch sites would be
 >possible and likely. I believe no nation on the planet has the launch
 >capability to go after the constellations at one time. The launch
 >facilities would be unlikely to survive a reload. So you might hit a
 >segment of GPS or Galileo's capability but you'd be hard pressed to
 >get a lot of them.

All excellent points, Adam.  However:

The Red Chinese do not have the capability to 
take out the GPS satellites TODAY.  They are 
working to have that capability within a decade 
and may well do so.  We also do not know what 
effect EMP will have on the GPS grid.  The recent 
test was just a first trial of what appears to be a lengthy program.

The Chinese would only take out the GPS 
satellites if war with the US were imminent.  It 
would be an act of war.  They would only do this 
to hinder our ability to bomb their cities and 
installations, which would also be an act of 
war.  I do not believe that the PRC is actively 
working towards war;  it simply seems committed 
to maintaining peace by being prepared for war.

US defense analysts have been quite concerned 
over this for the past decade or so.  That's why 
the military services continue to use celestial 
navigation as a back-up system.

Sobering thoughts.

msmall@aya.yale.edu
Cha robh b?s fir gun ghr?s fir!



Replies: Reply from mark at rabinergroup.com (Mark Rabiner) ([Leica] Re: GPS)
In reply to: Message from lrzeitlin at optonline.net (Lawrence Zeitlin) ([Leica] Re: GPS)
Message from marcsmall at comcast.net (Marc James Small) ([Leica] Re: GPS)
Message from abridge at gmail.com (Adam Bridge) ([Leica] Re: GPS)