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Some planets are tilted so their North and South Poles are not straight up and down. Earth is tilted a bit - about 23°. Uranus is tilted a lot - more than 90°. Mercury, on the other hand, is hardly tilted
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Mercury has a magnetic field. Its field is weak. Earth's magnetic field is tilted, and so is Mercury's. That means Mercury's magnetic poles are not in the same place as its geographic poles. Mercury has
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Mercury has almost no atmosphere. The planet's small size means that its gravity is too weak to hold down a normal atmosphere. There is a very thin atmosphere around the planet. Mercury's thin atmosphere
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Mercury is the only inner planet other than the Earth that has a significant magnetic field (220 nT). This field, along with the planet's high density and small size relative to the Earth, indicates that
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