- MAGNETIC FIELDS:
A Magnetic Field is created any time electrically charged particles spin around.
Certain elements, notably iron (Fe) and Nickel (Ni), contain many charged electrons that spin around and create magnetic fields.
- Earth's Magnetic Field:
The Earth's core is made mostly of iron and nickel, and the core spins as the Earth rotates on its axis.
The spinning of the Earth creates a magnetic field, approximately (but not quite) lined up with the axis of rotation.
The current location of the Magnetic North Pole is in the Arctic region of northern Canada.
Over time measured in hundreds of years, the magnetic pole wobbles and wanders, but its average position over time aligns very closely with the axis of rotation.
For any two magnets, opposite poles attract one another, and like poles repel one another.
(By convention, a magnetic compass needle that points North is called a "North" (or North-seeking) pole, so the magnetic pole in Canada is actually a SOUTH pole.)
- Van Allen Belts:
Beyond the limits of the atmosphere, the Earth is encircled by two (or sometimes more) Van Allen Radiation Belts. Each is approximately donut-shaped.
These belts are considered part of Earth's Magnetosphere. They are slightly tilted to align with Earth's magnetic field.
The Van Allen Belts are composed of charged particles, captured from the Solar Wind. Their rotation around the Earth creates a magnetic field.
There is a smaller Inner Van Allen Belt and a larger and more spread-out Outer Van Allen Belt.
The Inner Van Allen Belt extends from a height of about 1,000 to 12,000 km above the Earth.
The Outer Van Allen Belt is more variable; it extends from about 13,000 km to 60,000 km (or 3 to 10 Earth radii) above the Earth's surface.
(Other, smaller belts may exist temporarily from time to time.)
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