5 ms·

So what exactly does that mean? If I'm driving from Chicago to Milwaukee will my compass say I'm heading South?

bjelkeman-again 8y ago
The flip can possibly happen in a lifetime, but it probably takes thousands of years. But we have never observed it so we don’t really know how, but we know that it happens. https://en.m.wikipedia.org/wiki/Geomagnetic_reversal#Character_of_transitions https://en.m.wikipedia.org/wiki/Geomagnetic_reversal#Charact...
cartsagis 8y ago
Fun fact, the earth Northern Magnetic pole (ie the magnetic pole in the northern hemisphere) is actually the south pole of the magnetic dipole. So your compass actually is already telling you that you're heading south. But yes, the compass you have today will point south instead of north, but this can be solved by repainting which pole of the compass is red :)
faissaloo 8y ago
I'd guess it would cause the mass death of animals that use the poles to navigate.
- Tharkun 8y ago
  Wikipedia seems to suggest this is unlikely: > Hypotheses have also advanced toward linking reversals to mass extinctions.[47] Many such arguments were based on an apparent periodicity in the rate of reversals, but more careful analyses show that the reversal record is not periodic.[17] It may be, however, that the ends of superchrons have caused vigorous convection leading to widespread volcanism, and that the subsequent airborne ash caused extinctions.[48] (https://en.wikipedia.org/wiki/Geomagnetic_reversal https://en.wikipedia.org/wiki/Geomagnetic_reversal)
- deleted 8y ago
  [deleted]
zamalek 8y ago
During the reversal, it is thought that Earth would have multiple magnetic poles (much like Sol). These would gradually move over the planet resulting in effects as benign as auroras over the equator, or as disastrous as telluric currents powerful enough to ruin electrical infrastructure. > say I'm heading South After the reversal is complete, yes. During the reversal your compass could well be rendered useless (pointing toward your closest pole); assuming we're right about how the reversal would happen.
- toomanybeersies 8y ago
  I wonder what effect multiple magnetic poles would have had if they had occurred during the Age of Discovery (15th-18th centuries). I guess with celestial navigation it would've had less effect that one might think, but it certainly wouldn't have made navigation any easier.
hermitdev 8y ago
My car already gets confused in Chicago. Today, I was driving south towards lower Wacker, and my car thought I was driving alongside Navy Pier in the lake... Wasn't until I got clear onto 290 that it regained its senses.
devb 8y ago
Compasses manufactured for the northern hemisphere have extra weight added to the "south" end of the needle because the "north" end is partially being pulled toward the ground as well as the north magnetic pole. So your compass probably just wouldn't work at all.

The flip can possibly happen in a lifetime, but it probably takes thousands of years. But we have never observed it so we don’t really know how, but we know that it happens. https://en.m.wikipedia.org/wiki/Geomagnetic_reversal#Character_of_transitions https://en.m.wikipedia.org/wiki/Geomagnetic_reversal#Charact...

cartsagis 8y ago

Fun fact, the earth Northern Magnetic pole (ie the magnetic pole in the northern hemisphere) is actually the south pole of the magnetic dipole. So your compass actually is already telling you that you're heading south. But yes, the compass you have today will point south instead of north, but this can be solved by repainting which pole of the compass is red :)

faissaloo 8y ago

I'd guess it would cause the mass death of animals that use the poles to navigate.

Tharkun 8y ago
Wikipedia seems to suggest this is unlikely: > Hypotheses have also advanced toward linking reversals to mass extinctions.[47] Many such arguments were based on an apparent periodicity in the rate of reversals, but more careful analyses show that the reversal record is not periodic.[17] It may be, however, that the ends of superchrons have caused vigorous convection leading to widespread volcanism, and that the subsequent airborne ash caused extinctions.[48] (https://en.wikipedia.org/wiki/Geomagnetic_reversal https://en.wikipedia.org/wiki/Geomagnetic_reversal)
deleted 8y ago
[deleted]

zamalek 8y ago

During the reversal, it is thought that Earth would have multiple magnetic poles (much like Sol). These would gradually move over the planet resulting in effects as benign as auroras over the equator, or as disastrous as telluric currents powerful enough to ruin electrical infrastructure. > say I'm heading South After the reversal is complete, yes. During the reversal your compass could well be rendered useless (pointing toward your closest pole); assuming we're right about how the reversal would happen.

toomanybeersies 8y ago
I wonder what effect multiple magnetic poles would have had if they had occurred during the Age of Discovery (15th-18th centuries). I guess with celestial navigation it would've had less effect that one might think, but it certainly wouldn't have made navigation any easier.

hermitdev 8y ago

My car already gets confused in Chicago. Today, I was driving south towards lower Wacker, and my car thought I was driving alongside Navy Pier in the lake... Wasn't until I got clear onto 290 that it regained its senses.

devb 8y ago

Compasses manufactured for the northern hemisphere have extra weight added to the "south" end of the needle because the "north" end is partially being pulled toward the ground as well as the north magnetic pole. So your compass probably just wouldn't work at all.