Mercury's magnetic field is tilted by about 10°. Its magnetic poles and geographic poles are not, therefore, in the same place.
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The Magnetic Poles of Mercury

Mercury has a weak magnetic field. Like Earth's magnetic field, Mercury's dipole field is tilted with respect to the planet's spin axis. This means that Mercury's magnetic poles and its geographic poles are not in the same place.

Mercury has a global magnetic field that is about 1% as strong as Earth's field. Mercury's magnetic field is apparently generated by swirling motions in the planet's molten iron core, in a manner similar to Earth. Mercury has a very large iron core; it fills about 42% of the planet's volume as compared to 17% for Earth.

Mercury's dipole magnetic field axis is tilted about 10° away from its spin axis. That tilt is very similar to Earth's (~11°) and Jupiter's (9.6°), much less than the tilt at Uranus (59°) and Neptune (47°), and larger than Saturn's (< 1°). Because Mercury's magnetic field is tilted, its magnetic poles are not located in quite the same places as are its geographic poles.

Last modified May 29, 2009 by Randy Russell.

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