Earth’s Magnetic field formula or downloadable vector field

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darkdave3000
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TL;DR
Calculating magnetic field strength at points around the Earth.
I want to render the Earth’s Magnetic field in a software and simulate solar wind electron interaction with it. How do I calculate the magnetic strength and vector orientation at each point around the Earth up to thousands of km?

Is there a formula?

Or do I need to download a vector field from NASA?
 
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It is more complex than you think. Can you imagine a simple formula for this?

246797
 
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anorlunda said:
It is more complex than you think. Can you imagine a simple formula for this?

View attachment 246797
Is there a vector field file that I can download for this?
 
anorlunda said:
It is more complex than you think. Can you imagine a simple formula for this?
Cool image! Where did it come from? Maybe @darkdave3000 can get the data from the source (like if it came from a simulation in COMSOL or something)...
 
The image comes from

https://en.wikipedia.org/wiki/Earth's_magnetic_field#cite_note-selfconsistent-1
The references in the article may lead to some data files.

It may be a bit extreme because it is from a period of pole reversal. However, even in other periods, it is complex and non-uniform although not as extreme.

If you get away from the surface, the field becomes more regular, but still not simple. This image comes from the same Wikipedia article. That might be more suitable to solar wind studies.
But I'll wager that other PF members may be able to point to publicly available models or data sets.

Edit: I think it would also be fun to gaze inward. I recall mention of vorticies in the Earth's mantle giving rise to the Earth's field via the dynamo effect. As the vorticies twist and turn (on geological time scales) the field moves and distorts. That too would be fun to model.
 
anorlunda said:
The image comes from

https://en.wikipedia.org/wiki/Earth's_magnetic_field#cite_note-selfconsistent-1
The references in the article may lead to some data files.

It may be a bit extreme because it is from a period of pole reversal. However, even in other periods, it is complex and non-uniform although not as extreme.

If you get away from the surface, the field becomes more regular, but still not simple. This image comes from the same Wikipedia article. That might be more suitable to solar wind studies.
But I'll wager that other PF members may be able to point to publicly available models or data sets.

Edit: I think it would also be fun to gaze inward. I recall mention of vorticies in the Earth's mantle giving rise to the Earth's field via the dynamo effect. As the vorticies twist and turn (on geological time scales) the field moves and distorts. That too would be fun to model.
I couldn’t find any files via references from that page.
 
darkdave3000 said:
I couldn’t find any files via references from that page.

you went through every one of those 78 references + the "further reading + "external links" ?
 
Can you show me a few of what you found? Maybe I’m searching the wrong links.
 
Vanadium 50 said:
If you aren't willing to provide even the most basic answer to my question, why shouldn't everyone simply conclude you want us to do your research for you? You don't want help. You want us to do it.
I couldn’t find any files, vector field or otherwise.
 
anorlunda said:
The image comes from

https://en.wikipedia.org/wiki/Earth's_magnetic_field#cite_note-selfconsistent-1The references in the article may lead to some data files.
darkdave3000 said:
Maybe I’m searching the wrong links.
davenn said:
you went through every one of those 78 references + the "further reading + "external links" ?
I started skimming down the references in the linked article, clicking into a few, and then clicked into Lucky #13.

That landed me in a long list of FAQs about the subject, and seemed to be pointing to several models of the Earth's geomagnetic field. I started seeing that there are several models that are used, and data and simulations for each. I didn't spend a lot of time looking, but clicking into FAQ #4 about how to get some of the model coefficients got me to a page with one possible equation to use. You might see if you can base your simulations off of that equation, to get some preliminary data. You will also need to get some sort of data or model of the Solar Wind, I would think.

You may want to spend some time clicking through the different models that are mentioned in the FAQ list -- that should help you to understand more about how the geomagnetic field is modeled.

Part of the FAQs:
1563553627056.png


Clicking on the IGRF model in FAQ #4
1563553747040.png
 
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