In January 1984, the pilots of a Soviet Ilyushin-18 aircraft
flying over the Black Sea were astonished and terrified to see a fireball,
about four inches in diameter, in front of their airplane.
Then, as the Soviet news agency Tass reported, the fireball “disappeared
with a deafening noise, but reemerged several seconds later in the passengers’
lounge, after piercing in an uncanny way through the airtight metal wall. The
fireball slowly flew above the heads of the stunned passengers. In the tail
section of the airliner, it divided into two glowing crescents, which then
joined together again and left the plane almost noiselessly.”
The Russians had witnessed one of nature’s rarest and most
mysterious phenomena—ball lightning.
Detailed reports date back many centuries, Diane de
Poitiers, mistress of Henry II of France, is said to have been burned by a ball
of lightning that chased her around her bedroom on her wedding night in 1557.
One year earlier, eight people in England were reported to have been killed by a
“fiery, sulfurous globe” that rolled through a door.
Today, ball lightning is no longer a phenomenon of purely
natural interest, for scientists are now studying it as a possible new source
of energy. In Rotterdam, in the Netherlands, researchers have begun an
elaborate experiment that may lead to the production of electricity from
artificially created ball lightning.
The leader of the Dutch team, Gerard C. Dijkhuis, has proved
that the lightning ball is held together by forces that fuse its atomic particles.
If this fusion reaction could be controlled, ball lightning could be used to
generate inexpensive electric power.
The first step: produce ball lightning to order. Dijkhuis
had heard that sailors often report seeing the phenomenon following short
circuits occurring in submarine batteries, and bought from the Dutch Navy an
old system of 400 individual batteries.
Dijkhuis installed them in a shed on a dock in Rotterdam,
linked them together, and then short circuited the system. Success came in
1985, although the apparatus produced fireballs only four inches in diameter
and they lasted no more than a second. In subsequent experiments the scientists
hope to sustain the ball indefinitely and create a continuing source of power.
One of the greatest problems, the Dutch team faces, is that
no one can offer an easy explanation for ball lightning. Some researchers have
even suggested that it is an optical illusion, no more than an image left on
the retina of the eye following a conventional lightning flash. But the many
reports of seeing it inside buildings, where no conventional lightning was
visible, argue against this theory.
Two British investigators, Mark Stenhoff and Dr. E.R.
Wooding, have made a list of the characteristics of ball lightning, based on
more than 50 reports. Their analysis confirmed many properties of ball
lightning that scientists had previously only suspected.
For example, they found that in 69 percent of the cases ball
lightning is seen out-of-doors, although it can also occur in enclosed spaces,
such as the room of a house or, as the Ilyushin-18 passengers discovered, in an
airplane cabin. In 89 percent of the cases, the phenomenon appears during a thunderstorm.
But, intriguingly, the researchers found that about a third of the witnesses
had not seen it come from a conventional lightning flash.
A ball itself, Stenhoff and Wooding concluded, is about 10 inches in diameter, lasts about five seconds, and is as
bright as a 40 watt light bulb.
Occasionally, it seems to leave a pungent smell. In about a
quarter of the cases the ball lightning caused damage; a broken window, for
example, or scorched grass. More than half of the people who took part in the
survey said that the ball seemed to explode as it disintegrated.
But ball lightning remains a mystery, and a tantalising one
on that. Some scientists see it as far more than a possible source of energy.
Ball lightning, they contend, is plasma, rare on earth but common in the sun
and the stars beyond our atmosphere. Close study of its properties may offer a
key to a greater understanding of the universe itself.
However, such projects are likely to mean little to those
who happen to encounter the phenomenon. One lady in Florida did not pause to
theorise when a sphere of lightning “the size of basketball” rolled into her
house. Instead, she hit it firmly with her flyswatter.
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