Magnetic Pole Leaves Canada

[+BigFurryMonster]

http://geology.about.com/b/a/176740.htm

 

The north magnetic pole has wandered out of Canada's territory for the first time since about 1600. The pole meanders in a nearly random path at about 10 or 20 kilometers per year, and lately it has been going northward into the Arctic Ocean. The latest measurements have it out in the ocean heading for Siberia. Canadians are getting used to the new state of affairs.

[Kybra]

It's a bit rough when even the forces of nature want to leave the country

 

 

 

Actually thats a bit mean, I quite like Canada

[+EraSeek]

Every day it does an eliptical orbit of about 85 KM:

 

 

Here is it's long term track:

 

Edited June 26, 2005 by EraSeek

[+tabulator32]

Actually thats a bit mean, I quite like Canada

I understand their bacon is quite good.

[+Kordite]

You're GPSr only compensates for the movement of the pole as accurately as your last firmware update. To obtain the most accurate estimate of your current magnetic declination, check

 

http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp

[GlobeCachers]

aww man, it wont come to Californa... on the other hand, my GPSr would go haywire

[+TeamRJJO]

You're GPSr only compensates for the movement of the pole as accurately as your last firmware update.

The parameters in the navigation message broadcast by the satellites compensate for polar wander. Polar wander estimates are updated in the GPS Master Control Station once a week. This is completely independent of receiver firmware, by design.

 

Peace,

TeamRJJO

[+reveritt]

You're GPSr only compensates for the movement of the pole as accurately as your last firmware update.

The parameters in the navigation message broadcast by the satellites compensate for polar wander. Polar wander estimates are updated in the GPS Master Control Station once a week. This is completely independent of receiver firmware, by design.

 

Peace,

TeamRJJO

Why should the peregrinations of the magnetic poles have any effect on GPS navigation? Surely the ephemerides of the GPS birds do not depend on the position of the poles--yes?

[+TeamRJJO]

Why should the peregrinations of the magnetic poles have any effect on GPS navigation? Surely the ephemerides of the GPS birds do not depend on the position of the poles--yes?

The range measurements used to generate orbit models of the sattelites are taken in Earth-centered-Earth-fixed coordinates. When the navigation message is constructed, a coordinate transformation to a Keplerian element set is performed. In order to be able to accurately transform the Keplerian elements back into a form usable by your GPSr, the elements must be adjusted for polar wander. This gets done in the navigation message so that the user doesn't need to bother with it.

 

Peace,

TeamRJJO

[+Ed & Julie]

Why should the peregrinations of the magnetic poles have any effect on GPS navigation?  Surely the ephemerides of the GPS birds do not depend on the position of the poles--yes?

The range measurements used to generate orbit models of the sattelites are taken in Earth-centered-Earth-fixed coordinates. When the navigation message is constructed, a coordinate transformation to a Keplerian element set is performed. In order to be able to accurately transform the Keplerian elements back into a form usable by your GPSr, the elements must be adjusted for polar wander. This gets done in the navigation message so that the user doesn't need to bother with it.

 

Peace,

TeamRJJO

Lots of purdy words there. You must have went to skool or sumthing.

[+Kordite]

In a previous posting in the GSP units and software area (link) I asked about whether magnetic declination information was broadcast in the GPS signal and was told that those tables are located in the firmware.

 

Now, I wouldn't hink an 85km wobble would make much of a difference but is it taken into account when I ask my GPS to give me a magnetic bearing?

[QuigleyJones]

It'll come back, It always does.

[+reveritt]

... In order to be able to accurately transform the Keplerian elements back into a form usable by your GPSr, the elements must be adjusted for polar wander. This gets done in the navigation message so that the user doesn't need to bother with it...

Why must the elements be adjusted for polar wander? The resulting Lat/Lon have nothing to do with the location of the magnetic poles. The only time that the magnetic pole has any relevance (as far as I can see) is when magnetic declination is applied to get a bearing, and that is optional, and performed by the GPSr.

[+The Leprechauns]

A Poem for Canada

 

If you love something, set it free.

If it comes back to you, it's yours.

If it doesn't, hunt it down and kill it.

[Team See More]

It's no wonder that the pole left with the way you've been treating it. Leaving it out in the cold, and basically ignoring it. The real question is what took it so long to come to it's senses?

[+Greymane]

What are the Poles doing in Canada anyway?!? Send them back to Poland where they belong!

 

(Or, you can send 'em down to the US as long as they bring their sausage along!)

Edited June 27, 2005 by Greymane

[+TeamRJJO]

Why must the elements be adjusted for polar wander? The resulting Lat/Lon have nothing to do with the location of the magnetic poles. The only time that the magnetic pole has any relevance (as far as I can see) is when magnetic declination is applied to get a bearing, and that is optional, and performed by the GPSr.

Here's a link that explains it much better than I can:

 

http://www.geo.ucalgary.ca/~wu/TUDelft/Rot...r%20wander'

 

Peace,

TeamRJJO

[+bunkerdave]

"If you love something, set it free...."

 

I guess we can't log it, since there are now neither virtuals, nor moving caches allowed.

[+reveritt]

Why must the elements be adjusted for polar wander?  The resulting Lat/Lon have nothing to do with the location of the magnetic poles.  The only time that the magnetic pole has any relevance (as far as I can see) is when magnetic declination is applied to get a bearing, and that is optional, and performed by the GPSr.

Here's a link that explains it much better than I can:

 

http://www.geo.ucalgary.ca/~wu/TUDelft/Rot...r%20wander'

 

Peace,

TeamRJJO

The presentation that you link to concerns variations in the rotation of the Earth, length-of-day, and movement of the geographic poles, not the magnetic poles.

 

It certainly makes sense that nutation and movement of the Earth's rotational axis would have to be taken into account by the GPS system, but I doubt if the location of the magnetic axis is a consideration.

[+denali7]

if that pole is moving, will it be difficult to stick a magnetic micro to it?

[+bunkerdave]

I can see where a wobbling earth would present some problems for the GPS system, but isn't that one of the reasons there is WAAS? To reconcile the ACTUAL locations on the surface with the locations being generated by GPS receivers using the satellite signals?

 

Not being an astro-physicist myself, and only scoring a 38 on the geek scale, I can't grasp what magnetic poles have to do with GPS.

 

NerdTest

Edited June 27, 2005 by bunkerdave

[+briansnat]

Some people have said I'm a magnetic Pole.

 

-Brian Sniatkowski

[+The Leprechauns]

Magnets can repel as well as attract. It all depends on which end is doing the talking.

 

So, Canada didn't want you anymore, and that's why you're in New Jersey?

[+cudlecub]

Was there a 35mm under the base of the pole or was it a hide a key?

[+Alan2]

Magnetic Pole Leaves Canada, Don't go looking for it!

 

Eh?