The Sun Vs Compass

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Hi I have just worked out the sun outage times and went out to check at the right time.

This surprised me, as it looks like my polar mount is about 3°e of 1W.

So what is the most accurate please, the sun or the compass?
 
Well, the compass is pointing to a magnetic north, rather than true north... so the sun!
 
And, depending where you are exactly, Somerset/Dorset is some 2° - 3° west of the meridian which will make 1° west 1° - 2° away from your true south.

Confused yet?!
 
PaulR said:
And, depending where you are exactly, Somerset/Dorset is some 2° - 3° west of the meridian which will make 1° west 1° - 2° away from your true south.

Confused yet?!
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Getting there :-) I am in Yeovil atm.
 
A standard error among those that are not familiar with working with a compass is the magnetic declination involved at that location.

And this declination or deviation changes over time, so it does get complicated, in some locations you add a few degrees to the compass, in some you deduct from the measurement, and as the magnetic North moves over time you have to correct for this.

Here is a link to tell you whats up at your location.

http://www.ngdc.noaa.gov/geomag-web/#declination

Now in the future there will be a pole swap, this means that the North pole will be were the South pole was, but most of us wont be around when that happens.
 
And the geosynchronous satellites are aligned on the true North/South geographical poles, so use the longitude at your location to find Due North and not magnetic north, Google Earth can do this for you, just turn on the "Grid" settings in the "View" menu.
 
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Is the "Sun vs Compass" near you and is it a Free House?
 
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