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In article , The Ghost In The Machine writes:
In sci.physics,

wrote
on Sat, 25 Nov 2006 18:55:54 GMT
:
In article , The Ghost In The Machine writes:
In sci.physics,

wrote
on Sat, 25 Nov 2006 06:50:09 GMT
:
In article , The Ghost In The Machine writes:
In sci.physics, Brad Guth

wrote
on Sat, 25 Nov 2006 03:07:23 +0000 (UTC)
1407a4225d28a022b8af765580ca2107.49644@mygat e.mailgate.org:
I guess an Earth w/o magnetosphere really doen't hardly matter,

In a way, you're right. An Earth without the magnetosphere would be
deadly during the daytime to all surface-dwelling life forms.

Really? Why do you think so?

It's a snap judgement admittedly, but my understanding is
that the magnetosphere of the Earth diverts the particles
approaching us from old Sol into the Van Allen belts, or
away from Earth entirely. However, I'd have to study the
matter, and these particles will probably not be fatal to
burrowing creatures (since most of them can't penetrate
rock) -- just the ones on the surface.

Nope.

The Earth atmosphere represents a shield equivalent to a 10m layer of
water, i.e something like 3-4 m of concrete or about 1m of lead.
That's more than you'll find on nuclear reactors. Only the most
energetic stuff has even a slight chance to get through it and stuff
that energetic won't be deflected by the Earth magnetic field either.
Not to mention that neither gammas nor neutrons are influenced by the
Earth magnetic field.

Note that life on the Earth surface in the vicinity of the Earth
magnetic poles, where you've no "magnetic shielding", is not disturbed
by this fact.

You could completely eliminate the Earth magnetic field and radiation
wise, on Earth's surface, it would've made no difference.

Interesting! Not that the shielding helps all that much
regarding less energetic radiation, to wit global warming.
:-)

Well, yes, the shielding is quite transparent to visible radiation.
That's why visible radiation is visible.

But at least we won't have to worry about the coming
pole flip. (It might be 20 years, or 20,000. I frankly
don't know, but AIUI the magnetic poles are showing signs
of doing something.)

It is a good thing that we've GPS now and don't have to rely on a
magnetic compass:-)

Mati Meron | "When you argue with a fool,
| chances are he is doing just the same"