Yes, perhaps my view is somewhat simplistic and speculative. However, there
is a lot of info out there regarding lightning and cosmic rays. For
example:
http://en.wikipedia.org/wiki/Cosmic_ray
and
http://www.damninteresting.com/?p=182
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of David Robbins K1TTT
Sent: Saturday, February 11, 2006 12:33 PM
To: reflector -tower
Subject: Re: [TowerTalk] lightning and insulated elements..
You are mixing up a couple things... 'cosmic rays from a strike' has nothing
to do with how strokes occur. There is some evidence for very large strokes
causing enough of a field to cause x-rays and maybe higher energy particles,
but that is after the fact.
The causing of strokes by cosmic rays is another thing all together. Even
with assistance from cosmic rays there is not enough potential to bridge the
gap from cloud to earth in one step. And if cosmic rays really did cause
enough of an ion trail all the way from the cloud to the ground then the
strokes would always be arrow straight, which obviously they aren't. the
phenomena of leader progression and streamers is very well documented now
and explains very nicely how the stroke channel grows in steps from the
cloud or ground and how the final connection is made to start the discharge.
This also works for strokes that progress a very long distance away from the
cloud, no need for cosmic help in either case.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Keith Dutson
> Sent: Saturday, February 11, 2006 18:17
> To: g3rzp@g3rzp.wanadoo.co.uk; garyschafer@comcast.net; 'StellarCAT';
> 'tower'
> Subject: Re: [TowerTalk] lightning and insulated elements..
>
> There was recently a program on PBS (Nova, I think) that reviewed
> current research on lightning strikes. This research is done mainly
> in the state of Florida. The potential in a typical thunder cloud was
> measured and found to be much less than required to draw an arc to
> earth. To help explain why an arc did subsequently occur, they
> brought in an expert on cosmic rays. He made some measurements and
> found evidence of cosmic rays from a strike.
>
> So now it is theorized that lightning is related to bombardment of
> charged particles from cosmic rays. The potential is increased by a
> huge amount when this happens. This theory also helps explain why
> sometimes a lightning strike will occur without presence of a thunder
> cloud, but often in air that contains large quantities of dust or
> other charged particles.
>
> If this is true, a strike event is truly unpredictable unless one can
> forecast when and where cosmic rays will strike a cloud.
>
> 73, Keith NM5G
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Peter Chadwick
> Sent: Saturday, February 11, 2006 6:21 AM
> To: garyschafer@comcast.net; 'StellarCAT'; 'tower'
> Subject: Re: [TowerTalk] lightning and insulated elements..
>
> K4FMX said:
> <A grounded tower is NOT less likely to be hit by lightning.
> Actually a grounded tower is a little more likely to be hit than a non
> grounded one.> Somewhere, some years back, I remember seeing some
> University work that suggested that the grounded tower had a
> discharging effect that reduced the chance of strike in the vicinity,
> but when a strike did occur, it had a higher probability of hitting
> the tower. Same as a lightning conductor on a building.
> Where to find the reference now is beyond me, though.....
> 73
> Peter G3RZP
> _______________________________________________
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