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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 is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA