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Become a nitrogen atom in the nitrogen cycle in our Traveling Nitrogen Classroom Activity Kit/Game. See all our games, activity kits and classroom activities.
This figure shows a model of the Earth's magnetic field being generated within the Earth.
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Gary A Glatzmaier (Los Alamos National Laboratory) and Paul H Roberts (University of California, Los Angeles).

Generating a Magnetic Field

Scientists believe there are two essential ingredients for generating a magnetic field. Those two ingredients are

A bar of iron can be made into a magnet by wrapping it with wires and running a current through the wires.

It is thought a planet, or a star, can generate a magnetic field if it has both of the two ingredients above. It must have enough magnetic material, and it must have currents moving inside the magnetic material. If a planet does not have enough of either of these two ingredients, it will not have a magnetic field. Planets which do not have magnetic fields include Venus (moves very slowly), and Mars (most the iron is on the surface, and not molten).


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Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The Magnetic Field

The force of magnetism causes material to point along the direction the magnetic force points. Here's another picture of how this works. This picture shows where the magnetic poles of the Earth are to...more

The Moon's Magnetosphere

Unlike the Earth, which has a protective shield around it called the magnetosphere, the surface of the moon is not protected from the solar wind. This picture shows the magnetosphere surrounding the Earth,...more

Earth's Magnetic Poles

Earth has a magnetic field. If you imagine a gigantic bar magnet inside of Earth, you'll have a pretty good idea what Earth's magnetic field is shaped like. Of course, Earth DOESN'T have a giant bar magnet...more

The Magnetic Poles of Uranus

Uranus has a strange magnetic field. The magnetic poles of Uranus are not at all close to the geographic poles of Uranus. The main magnetic field of Uranus is tilted 59 away from the planet's spin axis....more

The Magnetic Poles of Mercury

Mercury has a magnetic field. Its field is weak. Earth's magnetic field is tilted. So is Mercury's. That means Mercury's magnetic poles are not in the same place as its geographic poles. Mercury has a...more

Planetary Magnets

The Earth has a dipole magnetic field. This is when magnetic field lines point in a direction out of the South Pole and into the North Pole. Planets can also have quadrupoles (4 poles) and octupoles (8-poles)....more

Magnetic Fields Near Planets

A magnetometer is an instrument for measuring magnetic fields. Many spacecraft carry magnetometers to measure the magnetic fields around planets. When a spacecraft makes those measurements, what do the...more

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