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Comment by nostromo | Hacker News Reader

A lot of commenters are mentioning that the distance is greater than the distance by sea -- but the difference isn't as much as you might think.

Look at the shortest route between LA and Beijing and you'll see that you already go over Siberia and the coast of Alaska. http://www.gcmap.com/map?P=LAX-PEK

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Let me guess - some people don't understand cartographic projections? The shortest distance between two points is not a strait line on a map[1], especially when you are a long way from the equator.

[1] For most maps. Gnomic maps (image - http://en.wikipedia.org/wiki/File:Gnomonic_projection_SW.jpg) are designed to show the shortest distance as a straight line. I think the Dymaxion Map aka Fuller Map (image - http://en.wikipedia.org/wiki/File:Dymaxion_map_unfolded.png) is also OK.

The shortest distance between two points is not a strait line on a map

You're right. The shortest distance between two points lies on a 'great circle':

https://secure.wikimedia.org/wikipedia/en/wiki/Great_circle

Well, it's easy to understand cartographic projections without necessarily having an intuitive grasp of 'em.

> a strait line on a map

Pun intentional, right? ;-)

For those with WebGL, this is helpful to visualise:

http://data-arts.appspot.com/globe

Thanks for this, do you happen to have any other helpful links?

I got this simple projection from [1]: http://imageshack.us/f/24/laxpkg.png/

[1] http://www.btinternet.com/~se16/js/mapproj.htm

Which projection did you use for that?

The lat/long one at -179, 37, -5, which I guess is an oblique mercator.

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