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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.
I use GPS when I go hiking, but I would never trust it with my life; my compass, on the other hand, has been dropped, stepped on, crushed and generally ill-treated for about 15 years and has served me faithfully through all that time (although I have had to adjust the declination after a few of the really rough treatments). GPS is an incredibly useful tool, but it's never a good idea to trust your life to something whose batteries might go dead on you, especially when an excellent backup is easy to use, weighs only a few ounces, and can be had cheaply.
That's it. I'm no longer part of Team Sanity.
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?
I don't think it's that easy to read the fossil record and apply it to our situation. A species could easily get its population knocked down to 1/1000 of its former value, then recover over the course of a few centuries, without ever leaving a detectable trace in the geologic record. Also, it's often unclear why one species survived a mass extinction event while another went extinct, e.g., nobody knows why alligators and crocs survived the event that killed off the dinosaurs.
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?
I'm not a biologist, but IIRC, radiation-induced mutations are not a major driving force behind evolution. I think most evolution occurs simply by reshuffling the preexisting genes. And remember, there are plenty of chemicals in the environment that are mutagens. If radiation was a big factor driving evolution, it would be hard to understand most of the evolutionary history of life on earth, since most life on earth isn't terrestrial, and the nonterrestrial stuff (fish, underground bacteria,...) is shielded from radiation that comes from space. (Some radiation comes from the earth itself.) A lot of radiation doesn't penetrate very deeply, either, so it's a lot more likely to give you skin cancer than to mutate your sperm or egg cells.
BTW, I believe there was no measurable increase in mutations among the kids of the Hiroshima and Nagasaki survivors.
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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
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.
You're using a once in a million years event (albeit one that may last for a thousand years) to claim that compasses aren't reliable?
I suspect that if I go hiking tomorrow there is more chance of my GPS unit screwing up than the earth's magnetic field suddenly vanishing.
The real point of the post you are replying to is: if you are going to stake your life on a piece of equipment, make sure you have a backup. Preferably something that has different failure modes.
Actually, a pole -reversal- would hardly obsolete compasses. Now what upper atmosphere changes would do to the delicate sensibilities of the many intertwined GPS sats is... beyond the scope of this post.
The periodic mass extinctions don't usually coincide with magnetic field reversals. Field reversals are much more frequent than mas extinctions. The main body of empirical evidence for the field reversals are the alignment of magnetic domains in the ocean floor. However, the magnetic field described in this article would be weak and transient. It wouldn't have a fixed north and south. It would have multiple norths and souths, which themselves wouldn't be far more variable than the "normal" magnetic field. If you think about it, since it's being generated by the solar wind, which remains roughly fixed in relation to the sun while the earth spins around, the temporary magnetic field that would form during the reversal would probably remain more oriented to the solar wind than to Earth. It wouldn't be strong enough or constant enough to leave its mark on forming rock. The only thing they really have for it is models. It's a phenomenon that, assuming it happens, wouldn't leave a measurable trace. I guess we'll have to wait until it happens and see how things work.