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Magnetism

Magnetism is one of the main forces 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.

In most cases, planetary magnetic fields are made by currents of molten material which move around 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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Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, ranging from seismology, rocks and minerals, oceanography, and Earth system science to astronomy!

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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