Question
Thu February 07, 2013 By:
 

what is earths magnetic field?

Expert Reply
Thu February 07, 2013
Earth 's magnetic field (also known as the geomagnetic field) is the magnetic field that extends from the Earth's inner core to where it meets the solar wind, a stream of energetic particles emanating from the Sun. Its magnitude at the Earth 's surface ranges from 0.25 to 0.65 Gauss. It is approximately the field of magnetic dipole tilted at an angle of 11 degrees with respect to the rotational axis—as if there were a bar magnet placed at that angle at the center of the Earth. However, unlike the field of a bar magnet, Earth 's field changes over time because it is generated by the motion of molten iron alloys in the Earth outer 's outercore (the geodynamics).
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