[Avodah] Which way to Jerusalem?

[Micha Berger]

On Tue, Sep 07, 2010 at 12:43:27PM -0700, Simon Montagu wrote:
: It's easy to see from a globe that the same is true, lehavdil, for the
: distance from Alaska to Jerusalem. Does anyone happen to know in which
: direction Jews in Alaska pray?

We here in NY do not face ENE, even though that's the shortest route
around the surface of the earth. (Ever fly from here to Israel, going
over New England, Newfoundland, etc...?)

This is so counterintuitive to some, you might need to see a map Here is
an azimuthal equidistant projection of the world, centered upon NY City:
http://www.wm7d.net/az_proj/maps/1283891264.gif

Azimuthal equidistant projection is used by ham radio operators and
sattelite TV customers to aim their antennas to another point using the
shortest path.

We use plumb line directions, meaning -- you get to Israel by heading east
then south, or south than east, without looking at diagonals. Probably
because we care more about our symbolic acts being intuitive than being
correct. (Much like Birkhas haChamah.)

(The previous description could be replaced with a reference to "Taxicab
Geometry" <http://en.wikipedia.org/wiki/Taxicab_geometry>, which also
defines "distance", sometimes called Manhattan distance, in terms of
getting there on a grid only via right and left turns. IOW, spherical
geometry and spherical taxicab geometry give grossly different results.
But I doubt that helped much.)

If you really wanted shortest distance, you should face at a downward
angle, cutting a line *through* the planet...

Tir'u baTov!
-Micha

-- 
Micha Berger             Brains to the lazy
micha at aishdas.org        are like a torch to the blind --
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Fax: (270) 514-1507                 - Bechinas HaOlam