How to find North using Orion

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Gary
 
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How to find North using Orion

Postby Gary » Mon Aug 26, 2013 1:23 am

Have been asked this question over the years during sidewalks. Somehow keep forgetting to go back and find out the answer. Until now.

Draw imaginary line from Orion's "sword" to middle "belt" star. Extend line to horizon!

Image
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email: gary[at]astro.sg
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"The importance of a telescope is not how big it is, how well made it is.
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starfinder
 
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Re: How to find North using Orion

Postby starfinder » Mon Aug 26, 2013 1:52 pm

I think extending the line that runs from Orion's sword (the Orion Nebula) to the middle belt star (Alnilam) to the horizon to find north only works when the Orion constellation is near overhead. This applies to our equatorial regions. Otherwise, when Orion is for example near the horizon, extending the line points in the northern direction but it would run parallel to the horizon and not down to the horizon at due North.

Better to use the two Big Dipper stars (extending from Merak to Dubhe), when visible, to run a line down to the horizon at due North (again, equatorial regions only). This works at all times that these two stars are above the horizon.

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Gary
 
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Re: How to find North using Orion

Postby Gary » Mon Aug 26, 2013 2:43 pm

@starfinder - Yeah. That is true. Being asked this question a few times during sidewalks and apparently this method is being taught in the military forces. So this is more for satisfying my curiosity whether there is any truth in using Orion for finding north rather than recommending it over the better Big Dipper method when it is visible.
http://www.astro.sg
email: gary[at]astro.sg
twitter: @astrosg


"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.


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