[BITList] Great Circle & Rhumb Lines

[HUGH]

David,

I borrowed an apple from the kitchen, whence the following, which is the
only way as a non-navigator I can understand it.  Clearly a great circle can
be drawn (given a big enough pen) through any point on the globe. Every
great circle through one of the poles bears north or south, so not much help
in reaching most places.  Take any point other than a pole.  Of the infinite
number of compass directions that can be taken through that point, only two
will give a great circle, eg, SW/NE and NW/SE, the rest are rhumb lines.  So
the chance of a bearing from A to Mecca being on a great circle is quite
small and the Prof, as you say, is wrong.  I am prepared to be shot down.

Hugh.