[ntp:questions] NTP architecture recommendation
Richard B. Gilbert
rgilbert88 at comcast.net
Sun Aug 19 19:37:45 UTC 2007
David J Taylor wrote:
> Richard B. Gilbert wrote:
> []
>
>>I don't think that a 14 channel receiver would be useful! There
>>simply are not that many satellites! The last I knew, there were 27
>>NavStar (GPS) satellites in orbit. Of these, about seven are usually
>>above the horizon at any one time.
>
>
> Richard,
>
> There can be more than that - here's an example with 13 visible.
>
> http://www.david-taylor.myby.co.uk/software/wxtrack-extras.htm
>
> According to this source, there are 31 active satellites:
>
> http://celestrak.com/NORAD/elements/gps-ops.txt
>
> More in orbit, I expect, now dead.
> What do they do with decommissioned GPS satellites?
>
> Cheers,
> David
>
>
I suspect there's not much they can do with decommissioned GPS satellites!
You could probably launch 27 GPS satellites for the cost of one manned
mission to retrieve/repair one.
If you wait long enough, they will come down by themselves! It may take
a few hundred years. . . .
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