Talk:North magnetic pole

Latest comment: 2 years ago by 151.29.78.145 in topic E or W?

Terminology: "north" and "south"

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"When it was later understood that opposite poles attract, a terminological dilemma arose: the Earth's North Magnetic Pole and the pole of the magnet that was attracted to it could not have the same polarity."

This "terminological dilemma" only exists for those who have forgotten, or never knew, that the original names for the two ends of a magnet were "north-seeking" and "south-seeking". The Earth's magnetic pole in the northern hemisphere is thus a south-seeking pole, and the one in the southern hemisphere is north-seeking, just what you would expect. - ted@psg.com24.81.26.241 (talk) 04:53, 24 April 2008 (UTC)Reply

what is a magnetic force - a magnetic force are created when electric current flow.The greater the current,the stronger the magnetic field.The magnetic field B from the Lorentz Force Law ,and specifically from the magnetic force on a moving charge. The Earth North magnetic pole is the wandering on the earth's surface at which the Earth magnetic field points verically downwards.The north magnetic pole. — Preceding unsigned comment added by 24.190.68.96 (talk) 2008-04-15T01:22:59

Geomagnetic reversal: question

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The current explanation is this:

The Earth's North Magnetic Pole is the wandering point on the Earth's surface at which the Earth's magnetic field points vertically downwards (i.e. the "dip" is 90°).

That is correct now, but is it still correct before or after a geomagnetic reversal? If so, the North Magnetic Pole means the Earth's south-seeking pole, and it has been sometimes near the North Pole and sometimes near the South Pole. Or, does it mean the magnetic pole near the North Pole regardless of the polarity, which seems linguistically more correct? — TAKASUGI Shinji (talk) 10:10, 11 March 2009 (UTC)Kim Hanson (talk) 03:49, 24 September 2013 (UTC)Reply

Article needs to be reworded

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I feel this article needs to re-worded a lot.

From a physical magnetism perspective, there is a magnetic north pole, which lies in the southern hemisphere and vice versa. A north magnetic pole is a magnetic pole lying in the northern hemisphere and honestly such a terminology is of little use and is actually confusing for someone trying to gain an understanding.

There is a geomagnetic pole which is more of a defined rather than a physical reality. But the magnetic poles are both a reality.

Accepted that the concept of north and south are again based on convention, but again, once a north and south from a "magnetism"(physics) perspective are established, the magnetic north is in the south and vice versa.

This article is really poorly worded. —Preceding unsigned comment added by 24.177.113.191 (talk) 05:38, 7 June 2009 (UTC)Reply


Yes, this article is very poorly worded, and fatally flawed regarding the section on POLARITY. The author first correctly states that the "North" pointer of a compass is more correctly defined as "North seeking," but then draws the conclusion that, "Because opposite poles attract, the Earth's North Magnetic Pole is therefore, by this definition, physically a magnetic field south pole." That's pure malarkey. The reason why the North pointer of a compass is "North seeking" is because it is actually polarized South, and as the author correctly stated, opposite poles attract. No need to turn the world upside down to justify calling a North facing (South polarized) magnet pole a "North" pole. Although science and industry use the terms "North" and "South" to name magnet poles, this results in incorrect naming conventions. It would be preferable to restore the original "North seeking" and "South seeking" naming conventions, but that will probably never happen. Instead, we just have to realize that the "North" pole of a permanent magnet, or the North pointing arm of a compass needle, is actually North facing, or "North seeking" because it is in actuality a South pole in attraction to the Earth's North magnetic pole. Rickoff (talk) 07:21, 4 September 2009 (UTC)Reply

The terms "North Magnetic Pole" and "Magnetic North Pole" are both used, but "North Magnetic Pole" is arguably the more logical and Google Book Search and Scholar Search both indicate a preference for it. It is common to distinguish the "ends" of magnets by labelling them "north" and "south" ("N" and "S"). The end of the magnet labelled "north" is the one that points to the Earth's North Pole. By this convention, the Earth's North Magnetic Pole would be labelled "south". This is all correctly explained in the article. Your opinion that this convention is "incorrect" does not alter the fact. 02:32, 16 September 2009 (UTC). —Preceding unsigned comment added by 86.134.9.108 (talk)

Pole reversal and spinning core

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I have deleted the bit which says that the core stops spinning and then spins round the other way to cause a pole reversal. This is rubbish. 203.184.49.84 (talk) 09:20, 13 January 2010 (UTC)Reply

Geomagnetic poles: clarification needed

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This article states:

The North Magnetic Pole should not be confused with the lesser known North Geomagnetic Pole ....

Unfortunately, confusion is exactly what results when I attempt to learn the difference between a magnetic pole and a geomagnetic pole from this article.

Is the following statement true? This is my very tentative understanding after studying this article:

The north magnetic pole and the south magnetic pole are not directly opposite each other on a globe. However, the north geomagnetic pole and south geomagnetic pole are always directly opposite each other. One way to visualize the relationship between the magnetic poles and the geomagnetic poles is this: If you were to orient a globe so that the north magnetic pole was aligned directly above the south magnetic pole, the topmost point on this globe would be the north geomagnetic pole, and the bottommost point would be the south geomagnetic pole.

If this statement is true, then perhaps adding it to the article might help to clarify things for some readers. — Lawrence King (talk) 01:18, 27 June 2010 (UTC)Reply

Illustrations

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The illustration of the Carta Marina would fit best under the History section. The first image on the page should probably be a map indicating the location of the Magnetic North Pole and possibly its movement over time. — Preceding unsigned comment added by 129.82.105.52 (talk) 17:39, 29 June 2011 (UTC)Reply

I have implemented this suggestion. Cavit2 (talk) 19:21, 20 June 2016 (UTC)Reply

Did you know there was a merger proposal?

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A few months ago, an editor proposed to merge South Magnetic Pole into North Magnetic Pole, but didn't document this proposal in this article or its talk page. (Which is probably why there has been no discussion.) I have removed this template, for the following reasons:

  1. It doesn't make sense to merge South Magnetic Pole into North Magnetic Pole, because the title would be misleading. Instead, if a merger occurred, both should be merged into a different article with a neutral title. Unfortunately, Magnetic pole would be too general, while Geomagnetic pole has a specific meaning.
  2. The main argument against a merger is that the articles also cover exploration of the poles, and that is clearly a local issue for each pole (supported by separate Wikiprojects for the Arctic and Antarctic).
  3. The argument for merging is that some aspects of the magnetic field are global, particularly the geomagnetic poles—these are determined by a fit to the global magnetic database. The link geomagnetic pole redirected to North Magnetic Pole, which seems a bit North-centric. I have addressed this problem by creating a new article, Geomagnetic pole, to cover that particular kind of pole and the geophysics associated with it. There is now no need to merge the articles.

RockMagnetist (talk) 01:06, 30 September 2011‎

2005 contradiction

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I was about to add "In 2010, it was at approximately {{Coord|80|N|104|W|name=Magnetic North Pole 2010. The positions given are actually the averages of daily loops in which the pole wanders as much as 80 kilometers.[1]" when I noticed this story is dated 2005; our estimated position for the pole in that year is much different. Before I make a silly edit, is there something I'm missing here? Wnt (talk) 17:51, 15 February 2012 (UTC)Reply

Simply pulling out a magnetic compass shows this doesn't seem right. Air navigation charts agree something is not right. For instance Calgary International claims a deviation of 15° east and Toronto Pearson shows a deviation of 10° west putting the magnetic pole somewhere near the Boothia Peninsula. Since magnetic lines of force don't line up as sweetly as we would like this could be off by quite a lot, but by a thousand miles? In fact one would expect a small west deviation from Calgary International. I checked Norman Wells, Yukon. It is 65° N by 127° W but shows a magnetic variation of 23° east of true north. Remember, pilots rely on this data so it definitely works that way. A better explanation of why this occurs would be a boon. — Preceding unsigned (sorry, forgot to sign, signing now >)comment added by Kim Hanson (talkcontribs) 03:44, 24 September 2013 (UTC)Reply

You're right, there should be more explanation of this. Some of it is in Earth's magnetic field, where you can find a map of declination. The main reason for the variation is that the Earth's field is only approximately like a dipole (i.e., a bar magnet at the center). There is a substantial non-dipole component; and over time, the field changes. It's not a contradiction - just a fact of nature. RockMagnetist (talk) 14:58, 24 September 2013 (UTC)Reply
No, the Earth's magnetic poles are caused by the spin of iron-nickel liquid in the core. This spin creates a dipole magnet. The spin is caused by a combination of the earth's spin on its axis and Lunar and Solar tides. The spinning mass of liquid metal is also subject to precession (like a gyroscope), which moves the position of the poles over time. The lunar tide is not in line with the earth's rotational axis, so the motion of the liquid metal is not in parallel to the earth's axis and friction creates the precession. The moving liquid metal is not exactly centered within the earth and the motion is more complex than a spin, so the center of the magnetic axis is not at the center of the earth.
Pole reversal is a hypothesis to explain the differences in direction of the magnetic alignment of sediments. But plate tectonics combined with a wandering magnetic pole is a more likely hypothesis. There is no known force to cause a magnetic pole reversal during the past 3 billion years.
The magnetic needle dip is unrelated to the word dipole (which just means a two-poled magnet. That section is scientifically incorrect. Drbits (talk) 22:37, 22 August 2018 (UTC)Reply
@Drbits: By "that section", do you mean North Magnetic Pole#North Geomagnetic Pole? You seem to be mixing up two things: a model of the geomagnetic field that is a kind of least squares fit for a sphere, and the physical origin. In the least squares model, a dipole field is the lowest term in a multipole expansion of a magnetic field. As for the physics, the right place for it is Earth's magnetic field#Physical origin. RockMagnetist(talk) 02:13, 23 August 2018 (UTC)Reply
@RockMagnetist:No, the section is North Magnetic Pole. You are correct that the earth's central magnetic field is a combination of moving fluids, including some turbulence. There are also magnetized rocks, magnetically permeable rocks and magnetically susceptible rocks that affect the local magnetic field. However, the dipole magnetism swamps the other issues in almost all cases. My issues were with the discussion of "Dip Pole" (which does not happen, because the North Magnetic Pole is actually deep underground and the magnetic field is broad at the surface), the discussion of the magnetic poles being off center, and the discussion of pole reversal.
Many people (including some geologists) believe that the magnetic poles can suddenly (in a matter of days) die out and reverse. The force required to do that would be astronomical. This is based on a few locations where the local ferromagnetic particles are aligned anomalously, often assumed to be caused by impact magnetization. However, meteorites can carry a strong ferromagnetic field and cause a region of anomalously aligned magnetic particles.
The North Magnetic Pole is at the surface and it is a dip pole. For example, we have the quote "the magnetic poles are the points at which magnetic needles become vertical" from the World Data Center for Geomagnetism. RockMagnetist(talk) 02:02, 25 August 2018 (UTC)Reply
To see the complex relation between the declination and the magnetic pole in Canada, see the following NOAA map. Cavit2 (talk) 15:14, 24 September 2013 (UTC)Reply

References

  1. ^ Brian Vastag (2005-12-15). "North Magnetic Pole Is Shifting Rapidly Toward Russia".

Project Polaris confusion

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The Project Polaris subsection currently includes the quote:

…we can agree on one point, and that is the presence of what we can call the main magnetic pole on northwestern Prince of Wales Island. I have accepted as a purely preliminary value, the position Latitude 72 degrees N and 100 degrees Longitude West. Your value of 73 degrees 15' and 99 degrees 45’ W is in excellent agreement, and I suggest you use your value by all means.

— R. Glenn Madill

followed by the statement that: (The positions were less than 20 miles apart.) What two positions were less than 20 miles apart? 72°N 100°W is more than 75 nautical miles from 73°15′N 99°45′W. Is it a final figure, as opposed to the the "purely preliminary" one, that is less than 20 miles from Klein's location? This needs clarification.

The reference given for this is the following note:

The citation to accompany the military award of the Legion of Merit to Klein reads: "First Lt. Frank O. Klein distinguished himself by exceptionally meritorious conduct in the performance of outstanding services to the United States as a navigator while assigned to the 42nd and 72nd Reconnaissance Squadrons from June 1946 to October 1949. During this period, the exemplary ability, diligence and devotion to duty of Lieutenant Klein were instrumental factors in the resolution of many complex problems of major importance to the United States. He instigated research, which established that the magnetic north pole was not at the location reported in textbooks and on maps and charts at that time. His research not only revealed a new magnetic north pole position, but also revealed the existence of additional so-called secondary or local magnetic poles. The superior initiative, outstanding leadership, and personal endeavor displayed by Lieutenant Klein reflect great credit upon himself and the United States Air Corps."

which has no bearing on the material. -- ToE 00:55, 8 February 2014 (UTC)Reply

I suppose that either there was a typo in the latitudes and they should have been 72°N & 72°15′N or 73°N & 73°15′N, or they were misread as such by whoever made the 20 mile comment. The material was all added in a single edit on 23:06, 3 June 2012, by User:Cinderkimberstammy (talk) (contrib) who is no longer active. In his response to User:RockMagnetist he indicated that much of the material was relayed to him orally by his then 90 year-old father, Col. Frank O. Klein, although his contribution does say that "Details of Klein’s special magnetic studies are explained in two books, “World in Peril” by Ken White and “The Secret Explorers” by Fred John Wack." Someone needs to access these references to verify the material (and sort out the "20 mile" error). -- ToE 01:32, 8 February 2014 (UTC)Reply

I have removed the Legion of Merit citation as having no bearing on the information of this article. (Congratulations to Lt. Klein on a job well done, but that citation does not belong here.) I have also emailed Cinderkimberstammy to see if he can assist us in figuring our what material is supported by the two books he mentioned, World in Peril by Ken White and The Secret Explorers by Fred John Wack. Does anyone else here have access to these? @RockMagnetist: This is your field. Some of the Project Polaris material does still belong in this article, doesn't it? -- ToE 13:17, 11 February 2014 (UTC)Reply

I've received copies of several pages of World in Peril, including pg. 179 (of ch. 27, "Terrestrial Magnetic Studies") which includes the R. Glenn Madill quote. There was a typo in our article; the latitudes in the quote are 73°N & 73°15′N. I will make the correction now. -- ToE 22:10, 21 February 2014 (UTC)Reply

Missing: New Data

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Why is there no new data on the current magnetic poles? I can not believe that 2007 was the latest/last measurement of the current pole position. Is there a reason why they don't measure it each year instead of every 10 years? We need new data to verify the old models. --2A02:8071:68B:201:74D1:E262:A93C:E34C (talk) 11:38, 6 May 2016 (UTC)Reply

E or W?

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@Artoria2e5: I feel that in three recent positions of the N pole (1990, 2000, 2010) W is misprinted in E. 151.29.78.145 (talk) 13:05, 20 January 2022 (UTC)Reply

There is an E also for the 2021 value above. Also, please check for a misprint in the values "156 W at 2021 and 162 W at 2020" (a too-strong non-monotonic behavior in longitude). 151.29.78.145 (talk) 13:21, 20 January 2022 (UTC)Reply

151.29.78.145 The data was hand-converted from the tabular file linked in the ref. The data itself does not specify the E or W (instead using a 360-deg notation), so it is possible that I have flipped the sign.

I should point out however the pole has crossed over to the other hemisphere recently, so the 2020 outlier you see is normal. Most likely I should flip all of the E/W since it does make sense for the older Canadian locations to be in the Western Hemisphere. Artoria2e5 🌉 14:39, 20 January 2022 (UTC)Reply

for the non-monotonic statement, I did a ridiculous error: I considered 2021 BEFORE 2020! Excuse me. 151.29.78.145 (talk) 16:55, 20 January 2022 (UTC)Reply
if the data are those listed in the reference that I have accessed, you have simply inverted E/W in all. I suggest (to avoid unhappy edits by readers that do not think two times) to state explicitly that the pole has changed hemisphere and that the swift drift in longitude is due to the smallness of the longitude degree at these latitudes. 151.29.78.145 (talk) 17:10, 20 January 2022 (UTC)Reply