Whether
lore is full of rare phenomenon. Amphibians
raining
from the sky happens when frogs, fish or small waterborne animals
are caught in a waterspout. They
are picked up and unceremoniously dropped off on land, assuming the
waterspout ventures to shore. I
remember once seeing a small fish in a puddle in my employer's
parking lot after a thunderstorm.
Then there are triple rainbows.
While double rainbows are impressive,
they're not that unusual. Triple rainbows are a big deal though
because you can only see two of the
rainbows with the naked eye; the third occurs behind you and is
obscured by the sunlight. They are so
rare that no convincing photographic
evidence even emerged until 2011.
A rare weather event also occurred in the Grand Canyon in 2014
when the entire basin of the giant
canyon was fogged in. As the ground
cooled after a hot day and cold, humid air rolled in, low stratus
clouds filled the canyon from the ground up. The result? The 277-mile
long, 18-mile wide and 1-mile deep canyon was completely filled with
thick, foggy clouds.
Another rare phenomenon is ball
lightening. Some people have been skeptical of accounts of ball lightening. Were these balls
actually lightning? The skepticism began to wane in 1963 when a group
of scientists flying from New York to Washington, D.C., witnessed a
blazing orb drift down the aisle and disappear through the rear of
the plane. That began their research.
While some people may believed they
didn't exist, I know better. Many years
ago during a thunderstorm when I was in elementary school a ball of
lightening about the size of a basketball passed through the
classroom window and exploded in a cloud of smoke. I also remember
my father, who worked on the railroad, telling me of the time he saw
a ball of lightening bouncing down the railroad track and exploding
in a cloud of smoke.
Ball lightning appears as glowing
orbs that seem to occur during thunderstorms, usually following a
lightning strike. These floating fireballs shine as brightly as a
100-watt light bulb and they can
be white, yellow, orange, red or blue in color and are typically
about the size of a small grapefruit, although sightings suggest they
can range in size from golf ball to beach ball. Emanating from the fireball are little tendrils that seem to jerk
the ball around and
they move
slowly and erratically and are followed by smoke trails that form
spirals around them. And after a moment, they disappear. There's
no scientific explanation for balls of lightning, although there are
several proposed theories.
Speculations about the cause have ranged from the existence of
standing waves of electromagnetic radiation to plasma clouds and from
short-circuiting power lines to St. Elmo's Fire. While no theory has
yet to explain ball lightning, a promising theory focuses on silicon.
The most popular current theory, proposed by John Abrahamson at
the University of Canterbury in Christchurch, New Zealand, suggests
that ball lightning is the result of a chemical reaction of silicon
particles burning in the air.
When lightning strikes the ground, silicon that occurs naturally
in soil combines with oxygen and carbon and turns into pure silicon
vapor. As the vapor cools, the silicon condenses into a fine dust.
The particles in this fine dust are attracted to each other by the
electrical charge created by the lightning strike, binding together
into a ball. The glow and heat come from the energy created as the
silicon recombines with oxygen in the air. And once the silicon has
burned out, the ball lightning disappears.
This theory also suggests materials such as aluminum and iron
metals may also cause the orbs, and that any atmospheric discharge,
not necessarily lightning, may explain why ball lightning has been
sighted near power poles, electrical fitters, and even active faults.
Researchers Antonio Pavao and Gerson Paiva of the Federal
University of Pernambuco in Brazil have been working with the silicon
hypothesis and believe they have verified the theory with silicon
substrate and a high-voltage arc. They applied 140 amps of
electricity to silicon substrate, which vaporized the substrate and
sometimes produced golf ball-sized fireballs.
Also, two scientists at Tel Aviv University accidentally created
ball lightning with a device they call a "microwave drill."
This microwave drill was made from a 600-watt magnetron taken from a
conventional kitchen microwave oven and a powerful microwave beam
capable of penetrating solid objects. The tip of the drill aims the
beam at a solid substance and creates a hot spot in the solid. When
the drill is pulled away from the hot spot, the drag produces a
fireball resembling ball lightning.
Recently researchers from Zhejiang University in Hangzhou, China,
have proposed that the bright glow of lightning balls is created when
microwaves become trapped inside a plasma bubble. At the tip of a
lightning stroke reaching the ground, a electron bunch can be
produced, which in turn excites intense microwave radiation. The
eerie orb-light glow is created when microwave radiation given off
during a lightning strike becomes trapped inside a plasma bubble.
While ball lightening usually appears during thunder storms, it has
been know to form inside closed rooms and, as mentioned above, inside
aircraft. Exactly how ball lightning seems to float through walls or
windows, however, is still up for debate.
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