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raaaid
04-28-2006, 02:25 PM
i studied in navigation that if you have a map from 1950 youl have to check in the map the yearly declination of the magnetic north and calculate the north for 2006

what recalls my attention is that this deviation doesnt oscilate according the maps it has a constant sense

my theory is that true north and magnetic north are varying and once true north and magnetic north coincide it will reverse magnetic field ( million years ago magnetic north might be in the equator)

from 1996 to 1999 magnetic field of the earth force went from 4.5 to 1.5 gaus so we would be about to face a 0 gauss and then reverse

i wonder if somone sells artificial magnetic field generators since cosmonauts switched off the artificial magnetic field of the ship and cosmonauts went insane

raaaid
04-28-2006, 02:25 PM
i studied in navigation that if you have a map from 1950 youl have to check in the map the yearly declination of the magnetic north and calculate the north for 2006

what recalls my attention is that this deviation doesnt oscilate according the maps it has a constant sense

my theory is that true north and magnetic north are varying and once true north and magnetic north coincide it will reverse magnetic field ( million years ago magnetic north might be in the equator)

from 1996 to 1999 magnetic field of the earth force went from 4.5 to 1.5 gaus so we would be about to face a 0 gauss and then reverse

i wonder if somone sells artificial magnetic field generators since cosmonauts switched off the artificial magnetic field of the ship and cosmonauts went insane

VW-IceFire
04-28-2006, 03:22 PM
While its true that the magnetic north is moving all the time its not true that when the magnetic and true north coincide that anything will happen. Why can I be certain about this? Because true north is a position on a map...its purely artificial and completely man made. If you go to the true north pole you will find nothing out of the orindary...your compass will still point to the magnetic north pole.

I would at this stage like to point out that I realize that the magnetic north pole is actually in the southern hemisphere and the magnetic south pole is in the northern hemisphere and infact the compass needle that is pointing north is infact pointing to the south magnetic pole as the compass is north. But thats confusing for the purpose of my argument so I left that out.

No extinctions or unusual weather patterns have been linked to periods where the magnetic poles reversed so it is not likely that the change will have any major effects on us or wildlife. While it is true that the magnetic field sheilds us from radiation...most scientists are happy to point out that most of the radiation shielding comes from the atmosphere and not the magnetic field. While both working in concert is better it isn't going to have a huge impact...or its not likely to as there are no records of it having impacts in fossil history.

Although its been written the the magnetic field does varry in intensity having a low value over the period of a few years does not indicate pole reversal is imminent. It is predicted to happen within the next few million years so we're "due" but probably not within our great grandchildrens timelines.

One things for sure...all those CRT monitors are going to be in for a rough ride http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">i wonder if somone sells artificial magnetic field generators since cosmonauts switched off the artificial magnetic field of the ship and cosmonauts went insane </div></BLOCKQUOTE>

You can degauss a ship but its still going to have a magnetic field. This part doesn't make any sense http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Monty_Thrud
04-28-2006, 03:46 PM

raaaid
04-28-2006, 04:45 PM
http://en.wikipedia.org/wiki/Image:Airplane_vortex_edit.jpg

a beatiful picture on a previous topic on lift

|CoB|_Spectre
04-28-2006, 05:15 PM
In the U.S., aeronautical charts are released at intervals throughout the calendar year. Besides the obvious changes in landmarks and addition of obstacles (i.e., radio and t.v. towers), the charts show the isogonic and agonic lines depicting magnetic variation due to the magnetic pole's movement. This magnetic variation must be taken into account when plotting cross-country flights for navigational accuracy. After all, most light aircraft do not have the luxury of a gyrocompass slaved to a flux valve, therefore periodic adjustment to compensate for gyroscopic precession must be compared to magnetic heading info.

Scen
04-28-2006, 06:02 PM
Ahh but we do have the luxury of buying a GPS. Problem solved for the most part.

MLudner
04-28-2006, 06:23 PM
That GPS cr@p won't do you a whit of good after the aliens shoot-down all the satellites. http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif http://forums.ubi.com/images/smilies/53.gif

There are 3 norths: Grid, Magnetic and True. Military maps always show the G-M Angle on the legend at the bottom. There are a few places - not many - where they all - or two - come together. Where I live the GM Angle is 14 degrees.

Z4K
04-28-2006, 07:45 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">true north is a position on a map...its purely artificial and completely man made. </div></BLOCKQUOTE>

I can't agree. The true north and south poles are measured positions - not arbitrary creations. If one stands there one won't notice the difference, but you'll be standing at one of the only two points on the planet where the axis of rotation intersects the surface. If you look straight up all day, you'll always be looking in the same direction (neglecting the planet's wobble).

There is absolutely no reason to think that the alignment of magnetic north and true north will cause the poles to flip, or the magnetic field to vanish.

raaaid
04-29-2006, 06:00 AM
i checked the wikipedia before asking here but didnt find the answer

if a map from 2000 says you have to add a mgnetic deviation of 1âÂº per year in 2360 it will mean a variation of magnetic north of 360âÂº but then there will be two special moments when true north and needle north will coindide exactly

whats wrong with this asumption id prefer not to ask my teacher, many people here must have studied navigation

raaaid
04-29-2006, 06:03 AM
and maybe in an ancient times needle north was even on the equator?

navigation was my fauvorite subject ever, shame i didnt pass