Questions tagged [geomagnetism]
Geomagnetism covers questions related to the Earth’s magnetic field, its origin, history and measurement. Use electromagnetism for more general questions on magnetism.
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Why is aurora borealis circular in shape when viewed from space?
These are some false color images of the northern lights captured by NASA's satellite Dynamics Explorer-1.
Image credits: Dynamics Explorer - 1 (DE-1)
Spin-Scan Auroral Imaging (SAI)
Photo Gallery
It'...
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Why does the Earth's magnetic field have an angle of 11.5°?
Does anybody know why the magnetic field of the Earth have an angle of 11.5°? According to a theory by Prof. Blackett, Earth has magnetism due to the rotation of the the Earth about its own axis. (...
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Is Earth's magnetic moment vector oriented parallel or antiparallel to the sun's magnetic moment?
Just curious how these two magnets are spatially related to?
And in case there is no any special preferred particular orientation, what is anyway their spatial orientation relation (relative angles)? ...
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How are multipolar expansion of earth magnetic field computed?
In the study of the geomagnetic field, an expansion in spherical harmonics is used to represent the scalar magnetic potential: the first terms give the dipole approximation, then the quadrupole, etc.
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Do the currents of charged particles captured by Earth's magnetic field create their own magnetic fields?
Let me try to illustrate what I mean. Consider e.g. a Solar radiation storm (Solar particle event) where high-energy protons are hurled at Earth from Solar flares. I've tried to illustrate my ...
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Quantitatively, how much would radiation levels increase without the geomagnetic field?
Many, many popular science articles claim that if the Earth didn't have a magnetic field, then the much higher concentration of cosmic rays that reached the surface would cause health damage to humans....
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Is there a difference between the Earth's magnetic field and an applied magnetic field?
I want to use the HMC2003 3-Axis Analog Magnetometer and the manual says that it only works on applied magnetic fields like a permanent magnet so is there a difference between that and the earth's in ...
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Influence of magnetic field of earth
Is the magnetic field of a bar magnet influenced by the magnetic field of the earth. If so, will the magnetic field of bar magnet be different in a region where there’s no other magnetic field.
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Why is Earth's magnetic field not strong?
Why is Earth's magnetic field not as strong as the magnetic field that is artificially produced even though Earth's magnetic field is produced from an iron core that is very large? Wouldn't more iron ...
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What is the maximum possible averge power of the geomagnetic electric generator?
Earth's magnetic field strength varies from 25 to 65 μT on the surface. Therefore, magnetic energy is approximately $V\frac{1}{2} \frac{B^2}{\mu\mu_0} \approx 10^{\left (17,5\cdots 18,5 \right )} \...
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Is there a difference in Earth's magnetic field between day and night?
Is there a difference in Earth's magnetic field between day and night?
Magnetic Field
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What is ohmic decay and why does it happen in magnetized celestial bodies like stars and pulsars?
I've seen term "ohmic decay" mentioned in several papers (example) regarding the decay of magnetic fields in celestial bodies like planets, stars, and pulsars, but I can't seem find a clear ...
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Why is modelling the Earth as having geomagnetic poles useful?
I'm reading about geomagnetic poles and wondering what their signifcance is. It seems one (and perhaps the main) purpose of using this type of model is for understanding the aggregation of magnetic ...
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Have there been any experiments in which the Earth's electromagnetic field was used to do work?
Simply speaking using faraday's law to generate electricity with the use of earth's magnetic field.
I'm not talking about some revolutionary new way of generating electricity that would end our energy ...
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Whys is that the zonal (axisymmetric) magnetic field components of Saturn, Bϕ(longitudinal component taken to be ZERO
In a paper while calculating the magnetic field of Saturn longitudinal/azimuthal component is taken to be zero. why, has this to do with the dynamo model ?
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Would a Magnetic Polar Shift change the location of the Earth's Axis, and thus change the locations of the continents
Did a Magnetic Polar Shift cause the sahara forest to become a desert, because it shifted the location of Africa? Will it cause the continents to shift closer or farther from the equator, causing ...
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Magnetism in the original Cavendish Experiment (1798)
This is what Henry Cavendish writes on page 490 here
My next trials were, to see whether this effect was owing to
magnetism. Now, as it happened, the case in which the arm was
inclosed, was placed ...
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Is it generally accepted that Field Aligned Currents are caused by Force-Free Fields?
I am currently an undergraduate working on a project about FAC (Birkeland Currents) and it seems that most of the sources on the subject are very technical and hard for me to read (particularily ...
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Ideas for levitation using Earth's magnetic field and mu-metal [closed]
I'm not sure the idea works or not. Please answer it and its reason.
As shown in Figure 1, when the ASTM A753 Alloy2 magnetic shielding alloy is exposed to an external magnetic field, the applied ...
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Paleo-magnetism for the solar system over millions of years from the widmanstatten pattern?
I understand that the widmanstatten pattern (long fingerlike crystalline structure of iron nickel meteorites) is due to a slow cooling and solidification of asteroids over tens of millions of years.
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To what direction will a compass in a magnetic medium points? The direction of $B$-field or that of the $H$-field?
Question in title.
To avoid "same direction" answers, let's assume the B and H are pointing in different direction, i.e., the magnetic permeability is not a diagonal matrix. What direction ...
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Description of Van Allen's Belt and Magnetic Mirrors
The "Van Allen Belt" is a region near earth that concentrates a
high density of energy particles. The formation of this region originates in a phenomenon
called a magnetic mirror, when ...
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Earth's magnetic field lines with magnetic compass needle
Will the compass needle deflect in the opposite side inside the earth?
If so, where will be that location inside the earth?
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Why don't the Earth's oceans generate a magnetic field?
Many questions have been asked here about why the Earth has a magnetic field, e.g.,
What is the source of Earth's magnetic field?
How does Earth's interior dynamo work?
How can an ...
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What exactly are the 2 points where a magnetic needle becomes horizontal?
Textbooks and websites say:
A magnetic needle rests making different angles with horizontal when suspended at different places of the earth
In the explanation, they say that the magnetic needle ...
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Is Earth's North pole actualy a South pole?
As far as I am concerned, the compass is facing along the magnetic field lines on the Earth's surface which in turn points towards the North pole by its design. But for a magnet, the field lines go ...
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Will a neodymium magnet levitate on ice at Earth's North and South Pole?
Will a neodymium magnet levitate on ice at NP or SP? Asking just because these magnets are powerful and the Earth magnetism is fairly stronger at poles than at the Equator.
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Does the Earth's magnetic field reversal and the corresponding magnetostrictive stress and strain make any contribution to the Earth's oblateness?
If the changing magnetic field in a power grid's transformer can induce stress and strain on the transformer core, then can the changing magnetic field of the Earth, similarly, place stresses and ...
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Ferromagnetic field near a ring in Earth's magnetic field
Let's say I am trying to find out the effect that an iron ring has on the Earth's magnetic field (approximated to a uniform field at infinity). Can I solve it in 4 steps:
Find the magnetic field due ...
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Tilting of Earth rotational axis
In which way do the Earth's rotational axis tilted 23.5°.
see in the image we have been told that the axis of rotation of Earth is tilted 23.5° from the perpendicular to path.
But can anyone say in ...
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What will pole reversal cause to modern world and civilization?
I don't think it's just a matter of reorienting maps and recalibrating compasses.
In any case, how long does a inversion last? hours, days, weeks, years? If it lasts days or more.... would Sun fry ...
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Magnetic, geographic and geomagnetic poles
Can someone explain me in simple terms where and what are the magnetic, geographic and geomagnetic poles?
Some sites say that magnetic north pole is in the south and thus it attracts the south pole ...
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Magnet size vs field strength
Why is a compass not significantly affected by nearby (less than a couple meters) powerful magnets (such as those located inside home appliances and electronics) given Earth's magnetic field is just ...
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Does magnetic field exist throughout space?
My question is quite subjective and I could not find a suitable explanation to whether there is a magnetic field in space beyond earth .I read one of the article stating
Interstellar dust clouds have ...
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Origin of magnetic field of Earth
I have a hard time understanding why does earth have magnetic fields.
My textbook reads:
"The Earth's core is very hot and molten, and the ions of iron and nickel are responsible for Earth's ...
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Is there any observable change in Earth's magnetism to an observer in geosynchronous orbit?
I am in high school, and today my physics teacher was teaching us about the Earth's magnetism. This is the first time I've read about this topic, so take these questions as coming from a complete ...
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How do we know what the dipole moment of "The Earth Magnet" is?
It is given in my textbook and one other book(that I got from the library) that:-
...The earth has a magnetic dipole of dipole moment about $8.0\times 10^{22} \mathbf{ J.T^{-1}}$
The book doesn't ...
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Will superconductor levitate on Earth magnetic field?
We know the earth has both gravity and magnetism (which is very weak). Geomagnetism starts at the south pole and ends at the north pole. If I take a large sheet of superconducting material (very thin ...
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Can Earth's Magnetic Field Be as Less as -85μT and as Much as +70.46μT?
What did create the question?
I was analyzing a data set where the researchers have used objective data. They have calculated earth's magnetic field through sensors and that research was conducted in ...
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Why does a steel bar buried inside earth exhibits magnetic property? What will be the effect on it if we put it on the surface of the earth?
I'm thinking that it is because the magnetic field inside the earth is stronger than it is on the surface. Please correct me if I am wrong and give detailed solution.
Thanks!
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Low orbit space debris affects magnetic field? [closed]
Theory reduce earth temperature by removing low orbit junk and consolidating needed satellites
With all the space junk in low orbit, we effect both earth's magnetic field by moving metals into the ...
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How do rocks store information about Earth's magnetic field?
When a particular rock is being formed in a rift (by the solidification of magma, which is composed of ferromagnetic materials), the rock "stores information" about the Earth's magnetic field at the ...
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How does the aurora brightness depend on the distance from the poles?
I checked a few sites about aurora: http://www.aurora-service.eu/aurora-school/all-about-the-kp-index/ https://www.swpc.noaa.gov/products/aurora-30-minute-forecast https://www.swpc.noaa.gov/products/3-...
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Cancelling Earth's Magnetic Field. How effective is Helmholtz's coil?
If there is a pipe of very small radius with electrons moving inside it, and I need to cancel the Earth's Magnetic Field as otherwise it would affect the motion of the electrons (right?).
How ...
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Difference between Earth's magnetic field and Earth's gravitational field [closed]
I have a misconception about this. Are these really different? If so then how?
And one more problem is that, whether satellites orbit around the Earth because of Earth's Magnetic Field or Earth's ...
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Earth magnetic field space elevator. No cable [closed]
I have an idea that the space elevator can be build in the following conditions:
Not a classic theory. No cable. No Geostatic orbit. Not equator platform position
The possible platform / base ...
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What causes the vertical bands of light in an aurora?
I was lucky enough to witness a medium-strength aurora recently in Iceland (KP ~3). We saw the classic rippling arc of green light, which at times seemed to consist of smaller flickering vertical ...
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Why Earth's magnetism changes rapidly recently?
The magnetic north pole is wandering near Canadian coast. The rate of pole wandering increased recently. Which factors causing these?
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A strong neodymium magnet has no effect whatsoever on my phone compass. How is that possible?
If I hold a strong neodymium magnet near my iPhone while the compass app is running, there is no effect whatsoever on the compass bearing. It doesn't matter where I hold the magnet in relation to the ...
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How does the Earth's magnetic field protect it from the solar wind?
Several sources (see linked questions at the end) say that earth's magnetic field shields us from the solar wind.
The general consensus is that without earth's magnetic field, the atmosphere would be ...
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