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Earth has two north poles!. Geographic north and south: the ends of the imaginary axis line on which Earth rotates Magnetic north* and south: the imaginary points on Earth’s surface where the magnetic field lines leave (south) and enter (north) the planet
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Earth has two north poles! Geographic north and south: the ends of the imaginary axis line on which Earth rotates Magnetic north* and south: the imaginary points on Earth’s surface where the magnetic field lines leave (south) and enter (north) the planet *A compass needle points to magnetic north. A declination correction must be made to find geographic north.
Earth’s Magnetic Field • Is created by the inner core rotating inside the outer core, which creates a flow of charged particles • Is weak compared to permanent magnets • Extends beyond Earth’s diameter • Protects the planet from Cosmic Radiation and Solar Winds, which contribute to the natural phenomenon of the “Northern Lights”
Earth Protected by the Magnetic Field https://sites.google.com/site/earthsmagneticfield/the-truth-about-earth-s-magnetic-field/auroras-chapter-9
Aurora Borealis (north) and Aurora Australis (south) http://en.wikipedia.org/wiki/Aurora_(astronomy)
Using A Compass How Stuff Works: Compasses The red end of the needle points to magnetic north. The cardinal direction wheel rotates and should be rotated to match the direction of travel arrow. Then person should rotate, while holding the compass level so the needle can swivel, until the red needle and “north” line up. Walk in the direction of travel. The magnetic declination is the angle difference between magnetic and geographic north. Click NOAA’s Geophysical Data Center for geomagnetic data