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Re: Not so stupid question




Ever dropped iron filings around a bar magnet in water?
Notice that if you lay a disc on top of the magnet that
some of the iron filings are <<NOT>> parallel to the
surface and near the magnetic poles that are almost
PERPENDICULAR to the surface.  The earth's magnetic
field while not a perfect bar magnet inside a sphere is
close enough that this mind picture should help
establish that there is indeed an up,down, north,
south at the surface and gets more different from
north, south near the magnetic poles.

Bob



At 09:44 AM 12/26/1999 -0500, you wrote:
> 
>> > Is there any offset for elevation?
>> 
>> No. I heard of magnetic north; never heard of magnetic "up" though.
>> 
>
>I realize there was some humor involved here, but actually, the programs that 
>will give you your magnetic deviation (I have one I got from NOAA on my home 
>page...   http://www.megalink.net/~wejones/pgeomag3.exe )
>ask you for an altitude, which affects the results, so maybe there IS a 
>"magnetic UP"  :-) .  I at first thought that this meant elevation above sea 
>level, but I think it means above ground level, because it seems to work 
>properly only if I enter zero.
>   Anyway, it may make a difference if you are in an airplane, but not for an 
>antenna, unless you take your compass reading at the top of a REALLY tall 
>antenna.   :-)
>
>  I like the moon idea, but I prefer the sun. There are tables at 
>http://riemann.usno.navy.mil/AA/data/docs/AltAz.html
> (and many computer programs will give this too) 
>that give you the azimuth of the sun for any time of day.  I usually just
find 
>what time the azim is 180 and go look at the direction that the shadows are 
>falling, and that is north.
>
>
>
>
>
>**************************************
>*Bill Jones  N3JLQ  Sweden Maine     *
>* wejones@megalink.net               *
>* http://www.megalink.net/~wejones   *
>**************************************
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