View Full Version : Adjust your compasses...



squirrelcache
12-30-2009, 12:28 PM
It's true....if you use a compass....adjustments will be necessary. Earth's magnetic North is travelling Eastward, 40 miles per year. (http://news.nationalgeographic.com/news/2009/12/091224-north-pole-magnetic-russia-earth-core.html) Read the National Geographic article.

tat
12-30-2009, 01:54 PM
Actually, there is no need to adjust your compass. True north and magnetic north are quite different in Maine and have been for a long time. The difference is declination.

http://www.ngdc.noaa.gov/geomagmodels/Declination.jsp

It would be interesting to see how well this model predicts the future!

Haffy
12-30-2009, 06:45 PM
Just wait til 12/21/2012 if you think the poles are moving now....lol I saw it at the movies. :D:eek:

dubord207
12-30-2009, 08:55 PM
Not sure if Phil is making a legitimate recommendation here. I kept a good size boat in Rockland Harbor for 18 years. It had two Danforth Constellation compasses, one at the lower station and one on the bridge. I had the compasses "swung" every 3 years. The magnetic declination in Maine has been 17 degrees West for all those years and is still the same. While it does in fact change a little each year, I don't think it's enough to worry about the average compass. If you are using a standard magnetic compass ( they all are unless they're hooked to something electronic like a gyro, then your magnetic compass is 17 west of true north.

tat
12-30-2009, 10:16 PM
So, if the north pole is moving 40 miles per year toward Russia, where and how fast is the South Pole moving?

Ekidokai
12-30-2009, 10:18 PM
That explains it.

number seven
12-31-2009, 09:21 AM
I want to die while asleep like my grandfather, not screaming in terror like the passengers in his car.
I crack up every time I see this..(LOL)

Ekidokai
12-31-2009, 01:24 PM
I want to die while asleep like my grandfather, not screaming in terror like the passengers in his car.
I crack up every time I see this..(LOL)


Well, it's the truth.

squirrelcache
12-31-2009, 07:26 PM
I'm aware of declination. I was kinda joking about changing our compasses because I don't know how long it will be before our declination will change.

If you read the article you saw what I was commenting on: "A rapidly shifting magnetic pole means that magnetic-field maps need to be updated more often to allow compass users to make the crucial adjustment from magnetic north to true North."

Any good compass like my Silva Ranger comes w/a declination screw, to take out the guess work.

cano
01-01-2010, 12:09 AM
I'm aware of declination. I was kinda joking about changing our compasses because I don't know how long it will be before our declination will change.

If you read the article you saw what I was commenting on: "A rapidly shifting magnetic pole means that magnetic-field maps need to be updated more often to allow compass users to make the crucial adjustment from magnetic north to true North."

Any good compass like my Silva Ranger comes w/a declination screw, to take out the guess work.

What about birds using geomagnetic field for navigation. Do they need to update too?

number seven
01-01-2010, 02:25 AM
:DWhat happens when the magnetic poles switch,and it's coming.It's happened before.Food for thought:D