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Re: Communication thru P5-A

Cliff said:

>Ed, Chris and the group.   There is something wrong here in these
>calculations.  The distance to the moon is 238,000 miles average or
>397,000 kM.  Two way path length would be 794,000 kM.  That would
>result in a 46 db less loss to the moon unless I misunderstood
>something in the original assumption.

Cliff, you are assuming 100% reflectivity off the moon's surface.  400k km 
to the moon, bouncing off the moon and coming back is NOT the same as 800k 
km straight line.


With regard to the whole P5a "amateur communications" topic.

As far as I know (and this is based totally on my interpretation of the 
AMSAT-DL postings over the last several years), there is no intention to 
place an amateur transponder on P5. The range/power, and time delay issues 
have all been discussed.  Rather, P5 would support other European Mars 
missions by providing a relay link to the earth for other Martian 
satellites or surface probes  P5 would be designed and built by amateurs, 
and much of the talent, construction, and technology would overlap with the 
production of P3-E, a true amateur (transponder) satellite designed for 
elliptical earth orbit. Given P5's function, funding would undoubtedly have 
to come from non-amateur sources (universities, governments, space 
agencies, etc.).  Amateurs would provide their usual abundant "sweat 
equity."  Even though P5 would not be an amateur communications satellite 
in the traditional sense, the good will, experience gained, potential joint 
launch opportunities, cross-development of amateur projects, etc. that 
would likely flow from this project could be of considerable benefit for 
the amateur community.   ...at least that's how I see it.

  Stacey E. Mills, W4SM    WWW:    http://www.cstone.net/~w4sm/ham1.html
    Charlottesville, VA     PGP key: http://www.cstone.net/~w4sm/key

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