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Ball-lightning: Balls of Fire
Posted on Wednesday, October 11, 2006 (CDT) by Thoth
 On October 21, 1638, a strange darkness descended over Widecombe, Dartmoor. In the church of St Pancras some 60 people were worshipping at afternoon service, taking refuge from the thunderstorm outside.
According to written reports a sudden clap of thunder was heard and a "great ball of fire" ripped through the window. Part of the roof was blasted off as the fireball "bounced" through the church, burning dozens of the congregation and throwing them around like rag dolls, killing four. Then, with another deafening clap, the fireball disappeared without trace.
Many consider this to be one of the earliest (and most dramatic) records of ball-lightning, a rare phenomenon which has eluded scientific explanation for decades. Often described as "one of the big unsolved mysteries in physics", it is no surprise that ball-lightning has captured imaginations.
However, in
the absence of scientific explanation, it has become the domain of
alien-abductees and conspiracy-theorists, which has given it something
of a stigma within the scientific community. Certainly there are
scientists who are reluctant to accept its existence. But the sheer
number of sightings, combined with their apparent similarities,
suggests that ball-lightning is more than a myth.
Typically, observers
describe a small (around 1ft) luminous sphere which floats a little
above the ground for a while (usually under a minute). Almost all
sightings occur during stormy weather and end with the sphere either
disappearing in a violent explosion or simply fading from view.
There are some reports of
ball-lightning appearing in or beside aeroplanes – the "foo-fighters"
observed by some Second World War pilots are thought to have been
ball-lightning following the planes.
The majority of those who
witness ball-lightning escape unharmed, but there is evidence to
suggest that contact with the phenomenon can burn and kill.
There is no rigorously
tested scientific explanation for ball-lightning, but one of the most
popular is that proposed by New Zealand chemical engineer Professor
John Abrahamson.
Abrahamson's theory
explains ball-lightning as a rare consequence of regular lightning. A
lightning strike in soil "digs a hole in the ground, forming a very hot
channel" that cools to leave behind a tube, called a fulgurite.
The soil itself contains
silicon oxides and carbon. At sufficient temperature (3,000C) the
silica-carbon mixture can be reduced to elemental silicon (a process
that is commonly used in industry to extract pure silicon from sand).
The silicon is vaporised by
the heat of the strike and thrown upwards out of the ground "like a
smoker's puff". The vapour then condenses into a fine dust of
"nanoparticles" that slowly react with oxygen in the air.
Abrahamson proposes that
the nanoparticles form a "filamentary network" – a fluff made up of
tiny strands of silicon. A combination of electrostatic forces and air
currents are then responsible for shaping this "fluff" into a floating
sphere that releases energy as heat and light.
The layer of oxide on each
of the particles slows down the overall reaction, giving the lightning
balls a lifetime of up to 30 seconds and ending when all the silicon
has been oxidised.
Israeli scientists have put
the theory into practice. In February this year scientists at Tel Aviv
University created what they claimed to be a miniature ball of
lightning by firing high energy microwaves into a ceramic substrate.
They used the microwaves to
create a superheated "hotspot" which they drill up out of the material.
This creates a "hot drop" which, although short-lived, becomes a
convincing floating fireball.
Abrahamson continues to
refine his model and says his ambition now is to "systematically test
the particle theory, using the simplest experimental situations".
Copyright: Telegraph.co.uk
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No Comments Allowed for Anonymous, please register |
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Re: Ball-lightning: Balls of Fire
by FlamesOfTruth on Thursday, October 12, 2006 (CDT)
(User Info | Send a Message) | | This seems as if something true...It also bring light to a new aspect of dealing with the foes of the rightious. Mentality is might, Mind over matter at any given, to some how manipulate the lightening to a high concentration of silicon oxides and carbon. Then the presence the these lightning balls would be feared world wide?.....Interesting... |
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Re: Ball-lightning: Balls of Fire
by FlamesOfTruth on Thursday, October 12, 2006 (CDT)
(User Info | Send a Message) | | This seems as if something true...It also bring light to a new aspect of dealing with the foes of the rightious. Mentality is might, Mind over matter at any given, to some how manipulate the lightening to a high concentration of silicon oxides and carbon. Then the presence the these lightning balls would be feared world wide?.....Interesting... |
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