On Wed, 12 Nov 2008 17:20:21 -0800 (PST), wrote:

The anecdotal evidence is flawed because its conclusoin is based on
an observation without comprehensive study of what connected to that
boat, the content of soil beneath that boat, where the boat was
located in relation to earthed charges, etc.

OK, let me ask you this: 300 miles offshore in more than 5,000 feet
of salt water, lightning decides to strike a nearby wave top instead
of the well grounded 80 ft mast of an all aluminum boat.

Why?

Wayne.B wrote:

On Wed, 12 Nov 2008 17:20:21 -0800 (PST), wrote:


The anecdotal evidence is flawed because its conclusoin is based on
an observation without comprehensive study of what connected to that
boat, the content of soil beneath that boat, where the boat was
located in relation to earthed charges, etc.


OK, let me ask you this: 300 miles offshore in more than 5,000 feet
of salt water, lightning decides to strike a nearby wave top instead
of the well grounded 80 ft mast of an all aluminum boat.

Why?

Butterflies Wings or in this case, probably dust particles or rain
drops. The initial ionisation of the air immediatly below the leader of
the stroke is dependent on field strength but field strength in most
stuations falls off with the square of the distance so a rain drop of
lets say 3 mm diameter a meter from the tip of the leader has more
influence than that mast 100 metres away.

Its only if you have sharp enough edges and enough field strength to get
local ionisation on the rigging, St Elmo's fire being the extreme
example, that the difference between an 80 ft mast and a 8 ft wave
becomes significant. Waves dont have sharp edges . . .

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL:
'Stingo' Albacore #1554 - 15' Early 60's, Uffa Fox designed,
All varnished hot moulded wooden racing dinghy.

I saw something in some science news on the net shortly before I started
getting interested in this subject, I'll have to find it again but the gist
from a quick skim was that some scientists now believe that ground strikes
are following an ionization channel opened up one of the high energy cosmic
rays that are constantly bombarding the earth. The strike may divert to a
high object near the ground but the ray path could also lead it to the water
or a lower object.

--
Roger Long

On Thu, 13 Nov 2008 05:25:43 -0500, "Roger Long"
wrote:

I saw something in some science news on the net shortly before I started
getting interested in this subject, I'll have to find it again but the gist
from a quick skim was that some scientists now believe that ground strikes
are following an ionization channel opened up one of the high energy cosmic
rays that are constantly bombarding the earth. The strike may divert to a
high object near the ground but the ray path could also lead it to the water
or a lower object.


Great. Now it's all very clear.

--Vic

In article , Vic Smith wrote:
On Thu, 13 Nov 2008 05:25:43 -0500, "Roger Long"
wrote:

I saw something in some science news on the net shortly before I started
getting interested in this subject, I'll have to find it again but the gist
from a quick skim was that some scientists now believe that ground strikes
are following an ionization channel opened up one of the high energy cosmic
rays that are constantly bombarding the earth. The strike may divert to a
high object near the ground but the ray path could also lead it to the water
or a lower object.


Great. Now it's all very clear.

VBG Oh yes, that made me laugh. TY.

Justin.

--
Justin C, by the sea.

On Thu, 13 Nov 2008 20:34:47 -0000, Justin C
wrote:

In article , Vic Smith wrote:
On Thu, 13 Nov 2008 05:25:43 -0500, "Roger Long"
wrote:

I saw something in some science news on the net shortly before I started
getting interested in this subject, I'll have to find it again but the gist
from a quick skim was that some scientists now believe that ground strikes
are following an ionization channel opened up one of the high energy cosmic
rays that are constantly bombarding the earth. The strike may divert to a
high object near the ground but the ray path could also lead it to the water
or a lower object.

You don't get one track, you get an acre of them from just one
energetic cosmic ray. Within that two hundred feet, you would be
shaking the dice.

Casady

On Nov 13, 5:25*am, "Roger Long" wrote:
... but the gist from a quick skim was that some scientists now
believe that ground strikes are following *an ionization channel
opened up one of the high energy cosmic rays that are
constantly bombarding the earth. *The strike may divert to a
high object near the ground but the ray path could also lead
it to the water or a lower object.

Which says nothing useful. Cosmic ray does not construct a staight
conductive path through the air. Obviously lightning snakes in
various directions to earth; does not follow the straight path of a
cosmic ray. A microscopic path of ionied air might cause lightning
to snake slightly left rather than right. It is still constructing a
plasma path from cloud to earth because it must connect charges in
clouds (+ or 1) to charges on earth (- or+). If a conductive path
uses a boat, then a massive current later will follow that path
through the boat. Nothing will 'avoid' that strike.

Another myth promotes pointy items. Demonstrated in experiment is
that better protection uses blunt rather than pointy rods. Still when
lightning strikes, then either it does significant damage OR is
conducted harmlessly to beneath the boat. As the U of FL article
demonstrates, lightning can be conducted harmlessly if basic
guidelines are followed.