Talk:Earth's magnetic field

This is the talk page for discussing improvements to the Earth's magnetic field article.
This is not a forum for general discussion of the article's subject.

Put new text under old text. Click here to start a new topic.
New to Wikipedia? Welcome! Learn to edit; get help.

Article policies

Find sources: Google (books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL

Archives: 1, 2: 90 days

Earth's magnetic field has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.
Review: October 22, 2013. (Reviewed version).

Geology Top‑importance

	Geology portal Talk:Earth's magnetic field is part of WikiProject Geology, an attempt at creating a standardized, informative, comprehensive and easy-to-use geology resource. If you would like to participate, you can choose to edit this article, or visit the project page for more information.GeologyWikipedia:WikiProject GeologyTemplate:WikiProject GeologyGeology articles
Top	This article has been rated as Top-importance on the project's importance scale.

Physics Mid‑importance

	Physics portal This article is within the scope of WikiProject Physics, a collaborative effort to improve the coverage of Physics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.PhysicsWikipedia:WikiProject PhysicsTemplate:WikiProject Physicsphysics articles
Mid	This article has been rated as Mid-importance on the project's importance scale.

External links modified[edit]

Hello fellow Wikipedians,

I have just modified 2 external links on Earth's magnetic field. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 18 January 2022).

If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 00:51, 16 September 2017 (UTC)[reply]

External links modified (January 2018)[edit]

Hello fellow Wikipedians,

I have just modified 4 external links on Earth's magnetic field. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 18 January 2022).

If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 21:50, 22 January 2018 (UTC)[reply]

Request removal of outdated passage about Mars's atmosphere[edit]

The sentence "Calculations of the loss of carbon dioxide from the atmosphere of Mars, resulting from scavenging of ions by the solar wind, indicate that the dissipation of the magnetic field of Mars caused a near total loss of its atmosphere." from the "Significance" section is obsolete (from 1992).

This article Atmospheric Escape states that the vast majority of atmospheric stripping on Mars is/was caused by other processes not related to the magnetic field at all. This is properly supported by the MAVEN mission to Mars the paper to which is cited in reference 15 https://doi.org/10.1016%2Fj.icarus.2018.05.030. — Preceding unsigned comment added by 2003:E5:F10:FE05:F556:C879:F05D:D6E (talk) 16:57, 29 December 2021 (UTC)[reply]

As this change has been reverted a second time I want to explain this more verbosely. The second source supposedly confirming this sentence has literally nothing to do with mars' magnetic field at all. The first source is very old and only describes an assumption that has been disproven by the MAVEN mission.

The graph on page 8 of the paper I've mentioned above clearly shows that sputtering, which is the only process of atmospheric loss that is mitigated by the magnetic field, only represents an insignificant fraction of the total loss. DOI : 10.1016/j.icarus.2018.05.030

The idea that the solar wind strips away planets' atmospheres with too little magnetic field is outdated but is still stubbornly clinging on in many places. Here is a lecture explaining the current state of the art of our understanding of magnetic field interactions with solar wind https://www.youtube.com/watch?v=s7yGeWUyMkg 2003:E5:F02:1CD5:CC50:2B1:F735:FEFB (talk) 21:54, 5 January 2022 (UTC)[reply]

I agree that there seems to be something missing in the most common explanation. Wikipedia articles are intended to be based mostly on paraphrasing reliable secondary sources. The sources that you propose seem to be mainly primary sources. Wikipedia editors do not have the competence to say that it is time to discard the old explanation and take up the new explanation. If the new explanation takes hold and filters down to reliable secondary sources, then we can paraphrase those sources. It does not belong in the introductory section of the article. However, I would have no objection to adding a section about recent new explanations. Constant314 (talk) 00:09, 6 January 2022 (UTC)[reply]

I can understand that reasoning, however, this information isn't new. The MAVEN mission was in 2016. This particular source has already been incorporated into other Wikipedia articles like Atmospheric Escape which correctly presents the information from said paper.
And this is by far not the only paper correcting this general misconception.
It is very easy to find lots of articles about this somewhat recent shift in perception.

https://eos.org/research-spotlights/how-marss-magnetic-field-let-its-atmosphere-slip-away
https://www.aeronomie.be/en/annual-report/does-earths-magnetic-field-protect-our-atmosphere
https://web.ua.es/docivis/magnet/earths_magnetic_field2.html
https://www.space.com/11187-earth-magnetic-field-solar-wind.html
https://earthscience.stackexchange.com/questions/14915/does-the-magnetic-field-really-protect-earth-from-anything

I think this misconception is partly also due to another confusion. The earth's magnetic field indeed indirectly protects us from harmful UV radiation. Without the magnetosphere, the solar wind would dismantle the ozone layer. So it protects stuff on the planet but not the atmosphere itself.

The only sources I can find that still confirm this old concept of mars losing its atmosphere because of its lost magnetic field actually cite Wikipedia as their source.

Furthermore, the article is about "Earth's magnetic field", so that section is just off-topic at best anyway.
2003:E5:F02:1CD5:CC50:2B1:F735:FEFB (talk) 01:31, 6 January 2022 (UTC)[reply]

Earth's magnetic field magnitude[edit]

Hi, the second paragraph states: The magnitude of Earth's magnetic field at its surface ranges from 25 to 65 μT (0.25 to 0.65 G) [3]

This seems to be outdated or incorrect, as the magnetic magnitude in South Atlantic can be as low as 22μT. Source 1: https://en.wikipedia.org/wiki/South_Atlantic_Anomaly Source 2: http://www.geomag.bgs.ac.uk/education/earthmag.html#_Toc2075549

Perhaps a specialist can review... THX.. Shaberer-en (talk) 13:10, 14 February 2024 (UTC)[reply]

Wikipedia is not a reliable source, and I was not able to find the value 22μT in the second source. Can you point out where it is in the second source? Constant314 (talk) 19:18, 14 February 2024 (UTC)[reply]

Hi Constant314,

Thx for your response, sorry for the delay in replying.

the second source states 22,000 nT (=22μT)

http://www.geomag.bgs.ac.uk/education/earthmag.html#_Toc2075549

same this one (approx middle):

https://www.esa.int/Applications/Observing_the_Earth/FutureEO/Swarm/Swarm_probes_weakening_of_Earth_s_magnetic_field

While this one states 22,500 nT:

https://www.frontiersin.org/articles/10.3389/feart.2016.00040/full

(this is reference #1 in https://en.wikipedia.org/wiki/South_Atlantic_Anomaly)

THX! Shaberer-en (talk) 10:43, 25 February 2024 (UTC)[reply]

I saw it this time in the bgs ref. Looks good. Make the change if you wish, Constant314 (talk) 15:20, 25 February 2024 (UTC)[reply]

thanx - my first update! Shaberer-en (talk) 13:49, 2 March 2024 (UTC)[reply]