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Magnetism Overview - Windows to the Universe

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Magnetism

Magnetism is a fundamental force of nature, like the force of gravity. Like gravity, which causes objects to be attracted to each other, magnetism causes magnetized objects to be attracted to each other. The force of magnetism comes from the properties of electric charges.

In most cases, planetary magnetic fields are produced by currents of molten metal alloys which circulate deep within a planet.

An example of the force of magnetism at work is the magnet from your kitchen which sticks to the refrigerator door.

On Earth, a simple compass can always be used to detect the presence of the magnetic field of the earth around you, as well as any other nearby magnetic field.


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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF