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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Historical Magnetic Variation/Declination
From: Frank Reed CT
Date: 2004 Jun 19, 21:28 EDT
From: Frank Reed CT
Date: 2004 Jun 19, 21:28 EDT
Brooke C wrote:
"I'm not sure what yo mean by "regions of high field inclination"."
Regions close to the magnetic poles where the field lines are nearly vertical. If you have a multipolar field, like the sort of field you might have during a polarity reversal, then you will have a number of poles scattered around the globe possibly in places that would be inconvenient.
Since you certainly seem to know your sensors (I enjoyed your web page very much), in this "what-if" scenario where the field becomes multipolar, could one design a magnetic compass that would yield useful directional information (like standard compass bearing) even very close to a magnetic pole? If you had to cross an ocean where a magnetic pole is right in the middle of your trackline, could you have a compass that would yield useful information all the way across?
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
"I'm not sure what yo mean by "regions of high field inclination"."
Regions close to the magnetic poles where the field lines are nearly vertical. If you have a multipolar field, like the sort of field you might have during a polarity reversal, then you will have a number of poles scattered around the globe possibly in places that would be inconvenient.
Since you certainly seem to know your sensors (I enjoyed your web page very much), in this "what-if" scenario where the field becomes multipolar, could one design a magnetic compass that would yield useful directional information (like standard compass bearing) even very close to a magnetic pole? If you had to cross an ocean where a magnetic pole is right in the middle of your trackline, could you have a compass that would yield useful information all the way across?
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois