Quote:
Originally Posted by DavidNg
Hi,
How do people determine directions at the poles? from what I learn from high school physic classes compasses dont work at poles as N-S direction will be up-down, and how N-S-E-W directions still apply?
|
David, there are two sets of poles - geographic and magnetic.
At the geographic poles a magnetic compass will point at the magnetic poles so as long as you know where those are you can use that as a reference for longitude. However at the geographic poles all directions are N (south pole) or S (north pole). Once you move off the pole E and W have meaning.
At the magnetic poles a compass will spin uncontrollably, except for a dip compass which will point up/down.
A GPS would work, but commercial grade ones don't have the same accuracy when you are that far N or S because of the limited satellite visibility.