What's the difference between TRUE NORTH & MAGNETIC NORTH on a compass?
Which one should I rely on if I'm lost in a jungle for example?
- science_freakLv 41 decade agoFavorite Answer
There are two North Poles: the geographical and the magnetic North Pole.
The geographical pole is the point at 90° northern latitude. It is very near to the point at which the rotation axis of the earth passes through the surface. This is the North Pole that is shown on most maps.
The magnetic pole is the point were the magnetic field lines are vertical and enter the earth. This pole wanders around and is currently somewhere off Western Greenland at about 77°N 102°W (see http://sarbc.org/north5b.html).
True north is a constant and refers to the geographic North Pole. Magnetic north tends to shift and refers to the pole of the Earth's magnetic field. In mid 2002, true north and magnetic north were approximately 590 miles apart.
This handy article from hiking expert Doug Latimer (http://www.discoveralberta.com/Articles/Wilderness... the poles of the Earth's magnetic field are different from its geographic poles. Maps are aligned along true north, so hikers have to make adjustments when navigating by compass.
In navigation, the difference between true north and magnetic north is known as declination. All U.S. Geological Survey maps print relevant declination information, and the maps are updated every five years to account for shift. Hikers traveling in Northern California, for instance, have to make declination adjustments of roughly 18 degrees.
***As as far as relying on is considered there is no second thought than to rely on the geographical north or true north.... the reason is that almost all maps are made based on true north.
but if you are using a compass check where are you hiking and what is the declining adjustment (in U.S.A it is 18 degrees)you have to make to get the true north from magnetic north!!!Source(s): Ask.yahoo! and myself
- 1 decade ago
Also Magnetic north is always changing locations.
The Earth's North Magnetic Pole is the point on the Earth's surface at which the Earth's magnetic field points vertically downwards. This point moves gradually over time. The North Magnetic Pole is physically a magnetic field south pole. The North Magnetic Pole should not be confused with the lesser known North Geomagnetic Pole.
In 2001, the North Magnetic Pole was determined by the Geological Survey of Canada to lie near Ellesmere Island in northern Canada at 81°18′N 110°48′W / 81.3°N 110.8°W / 81.3; -110.8 (Magnetic North Pole 2001). It was estimated to be at 82°42′N 114°24′W / 82.7°N 114.4°W / 82.7; -114.4 (Magnetic North Pole 2005 est) in 2005. In 2009, it was moving toward Russia at almost 40 miles per year due to magnetic changes in the Earth's core.
Its southern hemisphere counterpart is the South Magnetic Pole. Because the Earth's magnetic field is not exactly symmetrical, the North and South Magnetic Poles are not antipodal: a line drawn from one to the other does not pass through the centre of the Earth; it actually misses by about 329.3 mi.Source(s): Wikipedia
- Vincent GLv 71 decade ago
The compass can only show the magnetic pole direction, which is somewhat the same general direction as the geographic one (which can be spotted by tracking the North Star) except if you are getting close to the pole. Maps (aviation navigation) would indicate the difference between the magnetic heading and the geographic one for the region they cover.
If you are lost, then either this is a clear night and you can see stars but cannot see your compass (because it is dark...) so you should rely on the North Star. If it is day and you cannot see the stars, then there is no way for you to know the geographic pole direction anyway, unless you have a GPS system, in which case you are *not* lost.
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- 1 decade ago
The true north is really the magnetic south, so the magnet is really on the south end of the compass. So, the "North"end of the compass really points south, but since it's "calibrated" so the present poles, they point in the same direction.
- XYZLv 51 decade ago
Magnetic north can shift around.
True north doesn't.
- 5 years ago
do you think our earth could be pulled away from the magnetic force any time soon