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North and South Poles. North Pole. The geographic north pole is defined as the direction pointing “up” using the right-hand rule. Axial Tilt. The axial tilt is the angle between the direction of Geographic North and the plane of the orbit (ecliptic). For Earth, this is 23.5 degrees.
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North Pole The geographic north pole is defined as the direction pointing “up” using the right-hand rule
Axial Tilt The axial tilt is the angle between the direction of Geographic North and the plane of the orbit (ecliptic). For Earth, this is 23.5 degrees.
Axial Tilt Planets have very different axial tilts. Uranus lies on it side. Venus is upside down.
Earth’s Magnetic Poles • Earth is like a bar magnet • This field is probably due to currents flowing in the Earth and is decreasing out at ~5% per century (decade?) • Compass Needles • A compass contains a small bar magnet for a needle. • The North pole of a magnet is the north-seeking pole - it seeks geographic North • Since North magnetic poles are repelled by North magnetic poles, this means there is a South magnetic pole at the North geographic pole