What is a great circle track?
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What is a great circle track?
Definition:
A great circle is a line of shortest distance between two points on a sphere (or a flat surface) with a constantly changing track direction as a result of convergence.
What i don't get is why it refers to sphere as apposed to the earth?
and also why you constantly change direction as a result of convergence?
A great circle is a line of shortest distance between two points on a sphere (or a flat surface) with a constantly changing track direction as a result of convergence.
What i don't get is why it refers to sphere as apposed to the earth?
and also why you constantly change direction as a result of convergence?
What i don't get is why it refers to sphere as apposed to the earth?
and also why you constantly change direction as a result of convergence?
To visualise this take a globe, try stretching an elastic band in a straight line between say LAX and London and see how the angle between the band and the meridians, your track, changes as you progress along the "route". If you get it right you "leave" LAX tracking to the northeast, somewhere along the route you will be tracking east, and near London your track will be southeasterly - but your great circle has always been a straight line.
( and before someone points it out there's at least one exception to the track changing direction rule - the equator).
Last edited by wiggy; 29th Jul 2012 at 10:51.
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