What is Earths magnetic field: Definition and 14 Discussions

Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from the Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in the Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo. The magnitude of the Earth's magnetic field at its surface ranges from 25 to 65 μT (0.25 to 0.65 gauss). As an approximation, it is represented by a field of a magnetic dipole currently tilted at an angle of about 11 degrees with respect to Earth's rotational axis, as if there were an enormous bar magnet placed at that angle through the center of the Earth. The North geomagnetic pole actually represents the South pole of the Earth's magnetic field, and conversely the South geomagnetic pole corresponds to the north pole of Earth's magnetic field (because opposite magnetic poles attract and the north end of a magnet, like a compass needle, points toward the Earth's South magnetic field, i.e., the North geomagnetic pole near the Geographic North Pole). As of 2015, the North geomagnetic pole was located on Ellesmere Island, Nunavut, Canada.
While the North and South magnetic poles are usually located near the geographic poles, they slowly and continuously move over geological time scales, but sufficiently slowly for ordinary compasses to remain useful for navigation. However, at irregular intervals averaging several hundred thousand years, the Earth's field reverses and the North and South Magnetic Poles respectively, abruptly switch places. These reversals of the geomagnetic poles leave a record in rocks that are of value to paleomagnetists in calculating geomagnetic fields in the past. Such information in turn is helpful in studying the motions of continents and ocean floors in the process of plate tectonics.
The magnetosphere is the region above the ionosphere that is defined by the extent of the Earth's magnetic field in space. It extends several tens of thousands of kilometres into space, protecting the Earth from the charged particles of the solar wind and cosmic rays that would otherwise strip away the upper atmosphere, including the ozone layer that protects the Earth from the harmful ultraviolet radiation.

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    North Magnetic Pole wandering away

    It has recently sped up to 30 miles per year, prompting a navigational update mostly for the North Pacific and Arctic regions. https://www.japantimes.co.jp/news/2019/01/12/world/science-health-world/north-magnetic-poles-movement-forces-unprecedented-navigation-fix/
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    Quantum Locking and the Earth's Magnetic Field

    Don't know if this is the right place to post this, but it seemed like the best place to start. I'm wondering how much stronger would the Earth's magnetic field need to be in order to make quantum levitation using Earth's magnetic field alone a possibility. Bonus: Effects the change in strength...
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    Loss cone opening angle

    Homework Statement Hi! I need to find the opening angle of the loss cone at a given altitude, when the magnetic latitude is 65 deg. Homework Equations See below The Attempt at a Solution First, I used the following equation to calculate the magnetic field at a given altitude...
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    Could earths magnetic field help cause/effec Tornadoes, and lighting?

    I was wondering if anyone knew of any research done on if there could be a connection between Earth's magnetic field and some of our planets less understood weather phenomenon like tornadoes and lightning. From my understanding the most excepted theory is that lighting is caused by charged...
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    Generating elctricity from earths magnetic field

    Q: Is it possible to generate electricity by locating a coil at one of Earth's magnetic poles? By grounding to the Earth a lead out to a load. Maybe Earth's rotation and the coil at some elevation just off the center of magnetic flux lines entering the earth. Would this cause flux lines to...
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    Cancelling the Earths magnetic field

    Homework Statement A researcher would like to perform an experiment in a zero magnetic field, which means that the field of the Earth must be cancelled. Suppose the experiment is done inside a solenoid of diameter 1.0{\rm m} , length 5.0{\rm m} , with a total of 9000 turns of wire. The...
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    Could I use electro magnets to repulse the earths magnetic field to levitate?

    I have this idea that I could use some electromagents that wen I run current through will repulse the Earth's magnetic field and that the higher voltage(or whatever electrical unti I decide to use) would send and object farther away from the ground and that the lower current would bring it...
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    Earths magnetic field and core

    How can random electron currents in the Earth's core create a ordered magnetic field? What makes a current in the Earth be north or south what is the difference between a north current and a south one? How come if the magnetic field is strongest at the centre of the planet how come where it...
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    Earth's Magnetic Field: Life, Solar Winds & Astronauts

    Hi I have two questions. 1. is all life on Earth reliant on energy from the Earth's magnetic field- Iknow it protects us from solar winds. 2. do astronauts need pemf in their capsules or space staions?
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    The average emf created by the earths magnetic field.

    Homework Statement What is the average emf created by a 15 turn cable that is .5 meters in diameter, lies flat with the surface of the Earth and is flipped 180 degrees in 2 seconds? *Assume the Earth produces a magnetic field of .5 micro Tesla. Homework Equations e=-n*r^2*delta...
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    Earths Magnetic Field and solar winds

    Since the Earth's magnetic field helps to protect the Earth from a lot of the suns harsh treatments, do we also assume that in some degree light is also (possibly in very small fractions) also diverted by the magnetic field? If no, would it even be possible to assume that a very strong...
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    Earths magnetic field is changing

    I heard that a moving magnet creates a charge in a nearby wire. (can you see where I am going here?) If we were to wrap a gigantic wire around the earth, would we in-fact yield some energy and of what magnitude do you expect that to be?
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    Calculate earths magnetic field?

    How do I calculate Earth's magnetic field at a distance x from Earth's surface? Do I have have to think about Earth as a dipole and use the rate at the dipole weakens?
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    Exploring Earth's Magnetic Field: The Truth Behind Its Cyclical Changes

    I heard that the Earth's magnetic field changes every few thousands of years? is this true, if it is how does that happen