Yes, this is quite correct. However, a world-wide map centred on the North Pole seems to be unlikely to be used for this purpose! Also, I suspect the Loximuthal projection (which preserves distance from the central point) might be more useful. As you point out, the further away your target, the less likely precision in pointing is going to matter, but power varies inversely as the square of the distance.
BTW, Antarctica makes up 360 degrees of the circumference of the map requested!
Paul
>>> [log in to unmask] 18 January 2002 15:41:09 >>>
Surely one particular use of azimuthal equidistant projection maps is to
guide the orientation of radio transmission aerial systems, to beam signals
to particular places. Not generally centred on a radio transmitting station
at the North Pole, I grant you, but distinctly useful if one wants to get
the (widely different) bearings for setting a UK aerial system to beam to
Auckland, Wellington or Invercargill. (New Zealand occupies about 120
degrees of the circumference of such a circular map.) There are computer
programs available, I believe, to allow the construction of azimuthal
equidistant projection maps for any given co-ordinates of origin. It's a
long time since I was involved in that (and then only peripherally), so
perhaps others can take up the question from here.
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Andrew S Cook MA PhD FRSA FRHistS
Map Archivist, India Office Records
The British Library
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-----Original Message-----
From: A Paul R Cooper [mailto:[log in to unmask]]
Sent: 18 January 2002 14:11
To: [log in to unmask]
Subject: Re: Polar Azimutthal Equidistant Projection Map
I would be very surprised if anyone has published such a map - it would be a
cartographic nightmare, with almost no useful properties (it would be
neither conformal nor equal area). It would be interesting to know the
application - it may be that something else would be more suitable. However,
it would be relatively straightforward to produce one in almost any GIS
package, and the data for world maps are freely available. I suggest that
you point him in the direction of the geography or GIS department of his
local university. Otherwise, the web-site
http://www.remotesensing.org/packages/index.php may be of help - it has free
packages for plotting maps, and is the source for the best projection
package available (proj).
Paul Cooper, who maps the opposite pole!
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