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Solar Winds to Protect Earth During Magnetic Pole Reversal
me98411 writes "A study published in April, hinted at possible anamolies/reversal in Earth's magnetic field. This study found that there is an anamoly in a large patch near South Africa where the Earth's magnetic field points in the opposite direction. Now, according to New Scientist, this planet might be safe during reversal of poles due to formation of replacement field created by interaction with solar winds. Phew! I was worried I will not be able to use my compass." Even better than compasses not being obsoleted, we won't be bombarded with dangerous levels of radiation, or so the scientists say.
The solar winds, which are charged particles being moved by solar radiation, will prevent us from being hit with charged particles and solar radiation?
I like to place meaningful quotes in my sig, so people will know that I know what meaningful quotes are.
are from the Aeronautics and Astronautics
group at the University of Washington.
They also have nice slides on airplane/spacecraft design,
also in PDF here
I would have thought that that alone would indicate that field reversals are not exactly "disasterous" for life on Earth. Poor for human health, maybe, but it's not like we're facing mass extinction.
Actually, given that they're apparently able to identify eras of field reversal in the archeological record, I wonder if anyone has tried to correlate it with periods of extinction or rapid evolution? That would be more interesting to me - at least better than all of the speculation that seems to be going around.
"Phew! I was worried I will not be able to use my compass."
Oh yeah! I forgot about my compass not working! Silly me - I was too busy thinking about the possible massive upsurge of CANCER . . .
Phew! I was worried I will not be able to use my compass. And how does this article change that?
Bush and the Republicans are to blame for this!
Nice joke, but were you aware of the huge stack of magnets Bush is having set up at the science station on the south pole? He has errected a giant stack of iron-ferrite magnets a mile high with a magnetic field opposite to that of the Earth. Every day it gets higher. Apparently he is trying to speed up the reversal process, because it is rumored that durring a field shift special instruments can be used that make it easier to locate huge oil deposits under the earth, and these instruments are usually rendered useless by the Earth's magnetic field.
Just food for thought.
Not only has the magnetic north pole wandered by 1100 kilometres in the past 200 years, but its strength is dropping at a rate of 5 per cent a century. "This is the fastest decrease since the last reversal 730,000 years ago," Lesch says
I do find it interesting, I wonder if it could happen in the next 300 years or so?
Just because the solar wind will help produce a magnetic field in place of the Earth's natural one doesn't mean it'll point in the right direction. That compass may be just as useless with this field as it would with none at all. How will you feel when your compass informs you that you're traveling straight up?
"...and "a lower magnetic field means more radiation getting to the surface" may all sound like common sense..."
Well there was something on PBS that basically said the same thing. So it's not like a bunch of uninformed "flat earth" people have gotten ahold of the nation.
Anyway it doesn't really matter, because I'll be DEAD by then. World goes extinct? You all know were I can be reached.
During the reversal, there will be some magnetic fields left, but will be more random and spiratic than usual. Your compass will still point somewhere... but that won't have any correlation to where north is.
You can deflect something toward you.
See here for a complete definition of "deflection".
Now, one definition of "deflect" is "to turn aside", but that's not the same as "to turn away".
For example, in a CRT, the stream of electrons is deflected in order to write to the phosphor screen.
On some CRTs, this deflection is done by using charged plates.
The result is that the beam is deflected away from one plate, but toward the other.
The second plate deflects the beam as much as the first (actually, more so), and the deflection is toward the plate (i.e., the plate attracts the beam).
So, it is possible for a mass such as the Earth to deflect a stream of particles toward it.
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
The idea that the atmosphere/ionosphere can be used to set up counter-currents to exclude the solar wind from the planet (or at least shield it a lot) isn't really revolutionary. It's possible that the Earth-magnetospheres people aren't talking to the planetary folks enough, but the latter have been thinking about this for years. When you wonder how the solar wind behaves when it encounters, say, Venus, you're in this regime. It's also the basic category that includes those ever-sexy critters, comets.
I don't know that anyone has done a similar calculation for the Earth and if so if this new model is significantly different. But the basic idea has been out there. We covered it in my magnetospheres class 4 years ago and it was in the textbook well before that.
http://www.pbs.org/wgbh/nova/magnetic/
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Visit it, learn it, experience it...
Then LEAVE IT THERE......
Granted -- the current flock of satellites should be long gone by the time that happens, but this *will* raise the cost of LEO satelites over time.
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
The long trip to Mars will need strong shielding, just like a space station at the Eeath/Moon's L5 would need (not to mention the sheilding needed to get through the Van Allen belts). Of course a long term habitat would be served nicely by the 'free' sheilding.
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Reminds me of some weird all lyrics:
"Every thing you know is wrong, up is down, left is right, and short is long."
hehe
The reasoning sounds good, but the article doesn't address the fossil record at all. In layers of sediment laid down during magnetic pole reversals, hundreds of fossil species suddenly disappear and new ones appear. At least that's what I've read. Don't actual mass extinctions argue more strongly than theory?
How often does this happen?
Over the last 15 million years, the trend has been 4 reversals every 1 million years. However, this is not periodic. You could have one every 250,000 years, or possibly one in 790,000 years (the number of years ago this last happened) and then followed by 3 more in the span of 200,000 years. - Brad Clement of Florida International University.
How quickly will it happen?
Studies have suggested anywhere from 1,000 to 28,000 years are required to initiate and complete a reversal. However, core samples have suggested the last four flips took about 7,000 years to take place. However, it should be noted that near the equator the changes takes place roughly twice as fast as at the poles. Thus, no one human being will likely ever witness the full trauma of the event. - National Science Foundation
What will we use to determine direction? (The compass discussion)
This is relative to your purposes. If it is for purposes involving magnetism, the same methods for determining magnetic north should work (such as the old-school method of clearing gauss on a monitor), only not precisely accurately for any great amount of time. However, what we are all mostly concerned with is geographic north. Magnetic pole shifting is not going to change geography overly much...we think. There are many methods with which to determine direction using everything from the parts you were born with to fancy gizmos.
-The Libra
"Please be patient--The future will begin momentarily."
you people and your moronic anti-bush tirades have made me almost want to vote for him in November.