But they are sure that a compass needle lines up with the field. The tiny steel needle in your compass turns until it lines up with this magnetic field. When it lines up, one end of the needle points northe and the other points south. But don't expect to reach the North Pole if you travel in the direction your compass points. The North Pole is axis around which the Earth spins. A compass points to a different North Pole: the magnetic north pole. People who use compasses know just how much to change course if they want to travel to the true north or south--or anywhere in between.
Start your day with the top stories you missed while you were sleeping. Cookie banner We use cookies and other tracking technologies to improve your browsing experience on our site, show personalized content and targeted ads, analyze site traffic, and understand where our audiences come from. By choosing I Accept , you consent to our use of cookies and other tracking technologies. This fact means that the north end of a magnet in a compass is attracted to the south magnetic pole, which lies close to the geographic north pole.
Magnetic field lines outside of a permanent magnet always run from the north magnetic pole to the south magnetic pole. Therefore, the magnetic field lines of the earth run from the southern geographic hemisphere towards the northern geographic hemisphere. The geographic north and south poles indicate the points where the earth's rotation axis intercepts earth's surface. Consider holding a tennis ball between your thumb and forefinger and pushing on the side to make it spin.
The points where your thumb and finger make contact are the geographic north and south poles of the tennis ball's spin. A person standing on the equator is moving the fastest due to earth's rotation, while a person standing on a geographic pole does not move at all from earth's rotation. This difference between true north and the north heading on a compass is an angle called declination. Declination varies from place to place because the Earth's magnetic field is not uniform it dips and undulates.
These local disturbances in the field can cause a compass needle to point away from both the geographic North Pole and the magnetic North Pole. According to the United States Geological Survey, at very high latitudes , a compass needle can even point south.
By using charts of declination or local calibrations, compass users can compensate for these differences and point themselves in the right direction. Live Science.
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