The article is wrong. Maybe it was supposed to say 'the only terrestrial planet besides Earth...' and that was helpfully edited out at some point. Venus has no magnetic field. Mars doesn't have a global magnetic field, but does have spotty magnetic fields. The moon doesn't have a magnetic field, but there's speculation it may have once. All the Jovians have magnetic fields, Uranus' and Neptune's being particularly bizarre, with axes that don't intersect the centers of the planet, and wildly skewed to the axes of rotation. I don't think we know for sure whether Pluto has one; I'd guess not. See the classic Nine Planets Tour. Planetary magnetics are still a wide open field... no one's positive why planets do have magnetic fields. So no one can be positive why a given planet doesn't either. Edited 03-29-2002 03:12 PM
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