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North Pole Heads South
blamanj writes "Things are not looking good for Santa. First, news that it's getting warmer at the North Pole, and now, scientists report that the (magnetic) pole itself is on the move. 'Earth's north magnetic pole is drifting from North America at such a clip that it could end up in Siberia in the next 50 years.'"
But this site sure has them and this site has some too.
Read them. They are worth it.
It looks like there are two magnetic norths on the planet. Our current one looks like it is just the additive of the major and minor magnetic fields of the earth with their collective strengths oscillating over time... hence the apparent movement.
Could be interesting times (mental note: buy manual tin opener)
-- Intelligence is soluble in alcohol
The magnetic North Pole has never been a single point.
It has always been a general area, and at any given point of time, the *actual* North Pole would be somewhere in that area.
So, given that, this is not really surprising.
The geographic north pole is north by definition, the magnetic north pole is not - so it can head south.
James P. Barrett
Well, there's two ways of looking at it: either the Earth's magnetic poles are labelled wrongly, or EVERY OTHER MAGNET IN ALL HISTORY is labelled wrongly. Take your pick.
Compasses aren't labelled incorrectly. The North side of a bar magnet in a compass is labelled North because that is the way it points, not for its magnetic pole. They aren't saying, "Hey, this is the North pole of this magnet," they are saying "Hey, this side of the magnet always points North." Those are two completely different meanings.
Have you read the NASA article that you linked? It says nothing about mass extinction events and polarity reversals in earth's history, it appears to be talking about mars. Now if you look at this link http://image.gsfc.nasa.gov/poetry/venus/RevScience .html you would see that field does not coincide with mass extinctions. Furthermore when the last one happened paleontologists said there were no major changes in plant an animal life. So your mass extinction seems like a leap of imagination.
Well hmm according to http://image.gsfc.nasa.gov/poetry/venus/RevScience .html the earth's magnetic field does not cause mass surface life extinctions. If you would like to make an assertion like that, you really do have to back it up with something. In fact it will cause little change in the way things function, maybe a few thousand extra cases of cancer each year. Now if the field never came back and our atomosphere ionized, then we would be screwed.
Supercomputer simulations do not show that. According to the site: "Reversals take a few thousand years to complete, and during that time--contrary to popular belief--the magnetic field does not vanish. 'It just gets more complicated,' says Glatzmaier. Magnetic lines of force near Earth's surface become twisted and tangled, and magnetic poles pop up in unaccustomed places. A south magnetic pole might emerge over Africa, for instance, or a north pole over Tahiti. Weird. But it's still a planetary magnetic field, and it still protects us from space radiation and solar storms."
GPS Satellite are NOT in LEO. The GPS constellation orbits at 20,200 km. This is between the LEO sats: Iridiums (780km), the Hubble (569 km), the Space Station (351 km); but much lower than geosynchronous communications or weather satellites (35,786 km). They orbit the earth twice/day.
For a really cool visual demonstration, check out J-Track 3D over at the NASA web site. The GPS satellites are just about the only thing you find between the cloud near the earth, and the Clarke Belt.
- AlanH