Re: GPS + Pulsars + an apology/rebuttal

Quoting Roger Books <books@jumpspace.net>:

> On 23-Feb-02 at 11:29, Thomas Barclay (kaladorn@magma.ca) wrote:
> > Question:
> > Can we duplicate or fake a pulsar? If so, could 
> > we mess up people's navigation? Could we 
> > interfere with signals from a pulsar? Or cancel 
> > them via some form of interference? 
> 
> Well, you could fake it if you want to go back into
> the past 50 years or so and beam your fake to where
> your opponents will be.  :)
> 
> > When establishing our own space beacons (SPS 
> > - GPS in space), would we use some sort of 
> > pulsar like signal, but with more uniqueness?
> 
> 
> Who is going to put in beacons that will only be good
> after the signal gets across some large number of
> (light) years?

Erm. Us?

We have sent out messages that are unlikely to be read inside the next
50,000 
years. Sometimes people can be long-term about things...
  
> > You did not, in fairness, mention that the US can 
> > also (you did build, and did pay for, and do 
> > own - AFAIK - the constellation) turn off the 
> > feeds from some satellites entirely or probably 
> > even deactivate the whole shebang if it really 
> > wants to black out an area. 
> 
> We would have to shut down commercial air traffic
> to do this.  They are relying fairly heavily on
> it.

I don't know about in the US, but in Europe I was under the impression
that we