Thread: Lightning
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[email protected] LoogyPicker@gmail.com is offline
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First recorded activity by BoatBanter: Oct 2007
Posts: 7,892
Default Lightning

On Jun 17, 11:55*am, Short Wave Sportfishing
wrote:
On Tue, 17 Jun 2008 06:19:28 -0400, "Jim" wrote:

"Short Wave Sportfishing" wrote in message
.. .
Lightning strike yesterday evening...


http://www.swsports.org/images/Movies/strike.wmv


Sorry for the little wobble - I still can't figure out how to use that
stabilization thing - I know, I'm a putz.


Were those separate strikes? They look Identical.


I wondered about that myself as I'm not an expert on lightning strikes
even though for about 12 years I had three tall towers in the back
yard. *I was only an expert on preventing damage and repairing damage
I couldn't prevent. *:)

So I emailed one of my old friends who is a professor of meterological
sciences along with the video and he replied:

"It's called a secondary strike which can repeat the main strike as
many as 40 times. The time delay can be variable from nanoseconds to
miliseconds between the strikes. *It's one of those things we were
discussing the other day about "optical delusions" as the secondary
strikes will occur even when the main flash is still visible - you got
lucky in that one of the secondary strikes is in the millisecond
category. *I'll bet you anything it hit the old Fern's tower over on
W. Quassett Road right?

You also got lucky with the ionization flare - notice that little tiny
thin flash at the start of the strike? *That was the ionization trail
and from the looks of it, it started at the lake."

He was right which is why I aimed the camera in that direction because
that tower is like a freakin' lightning magnet.

Learn something new everyday although I think he mentioned it once in
a lecture of his I attended - I just forgot.

So it's the same as learning something new. *:)


Simply put:

Cloud-to-ground lightning (CG's)
A channel of negative charge, called a step leader, will zigzag
downward in roughly 50-yard segments in a forked pattern. This step
leader is invisible to the human eye, and shoots to the ground in less
time than it takes to blink. As it nears the ground, the negatively
charged step leader is attracted to a channel of positive charge
reaching up, a streamer, normally through something tall, such as a
tree, house, or telephone pole. When the oppositely-charged leader and
streamer connect, a powerful electrical current begins flowing. A
return stroke of bright luminosity travels about 60,000 miles per
second back towards the cloud. A flash consists of one or perhaps as
many as 20 return strokes. We see lightning flicker when the process
rapidly repeats itself several times along the same path. The actual
diameter of a lightning channel is one-to two inches