Great Balls of Lightning
Great Balls of Lightning
Have you ever heard of lightning in the shape of a ball that can float right through your window and into your living room?
We normally think of lightning as electricity that careens down from the sky and strikes the highest point on the ground that conducts electricity. It can be spectacularly beautiful if you’re watching from a dry point in the distance, but if you happen to get caught on a beach or a flat plain, you hope that highest point is not you.
Ball lightning is a bit different, and is an actual phenomenon that has been observed for thousands of years. It has been described as a luminous ball of light in various sizes, and it has been witnessed countless times over the ages yet has eluded scientific explanation.
These mysterious, hovering balls of light have been attributed to everything from a plasma bubble of electromagnetic energy to a figment of human hallucination. They have been reputed to run the gambit from being the inspiration for fantastic science fiction books to the cause of the Chernobyl nuclear reactor explosion in 1986.
For something which is dismissed by many scientists as not being real, there has been an inordinate amount of research invested in discovering what ball lightning is, if it is, and how it might be reproduced. Because it is so random, and has largely been seen only by casual observers who did not have the means to document it, ball lightning has been easy to dismiss. But in the last decade, it has gained some prominence in the curiosity of the scientific community.
First, what is lightning?
Most of us have been introduced to thunder and lightning from our earliest memories. You may have been taught to count the seconds between the flash of lightning and the sound of its thunder to guesstimate how many miles away the storm is. This is because sound travels more slowly than light, even though thunder and lightning are just different aspects of the same phenomenon. But what actually is lightning?
We all use electricity and while we mostly plug something into the wall and expect it to work, if we ask ourselves how that happens, we might recall learning that electricity is the flow of electrons along a wire, or conductor. We may also remember that electrons are negatively charged and that a negative charge is attracted to a positive charge.
In the same way, the lightning we see during a thunderstorm is the discharge of electricity. Static electrical activity is created when a negatively charged surface comes in close enough proximity to a positively charged surface. Static can be created by friction, such as petting your cat vigorously or rubbing your feet over the carpet.
When that friction loosens the surface electrons of your body, it creates a negative charge. Depending on how much charge is generated determines how great a shock you get when you touch metal or another object that conducts electricity, and it also determines how powerful the attractive force is and how easily it will jump to the positive surface. You probably did an experiment like this in middle school. But more recently, you may have noticed that on dry winter days when the heat has been running excessively, your dog might get a shock if you stoop to pet him after you’ve shuffled your feet over the carpet.
Clouds can build up charges, too, by the friction caused by water droplets bouncing off each other. The colder tops of the clouds tend to have a positive charge while the undersides of the clouds generally have a negative charge. When one charged cloud passes closely over another, or as the cloud’s internal charges gain intensity, there is a rapid release of energy which we see as lightning.
Lightning tends to be a roughly linear event intent on finding the easiest route to cancel out its electrical charge, although the path of least resistance may be a jagged streak to its destination. It may be seeking another cloud, the ground, or occasionally, it discharges into the air. There are an estimated 1 billion (1,000,000,000) joules of energy in an average bolt of lightning as it strikes the ground.
What is ball lightning?
Ball lightning is generally (but not always) associated with a lightning storm, and is thought by some to be a high-density plasma phenomenon. Witnesses have reported that it may fizzle out but it can also explode, causing significant destruction. It has been described in multiple colors, from white to blue to red.
Imagine if you saw a ball of light floating on the horizon? And what if that ball turned and came into your house, right through your closed window? This has been witnessed on several occasions!
As stated above, some say that sightings of ball lightning are, in fact, hallucinations brought on by transcranial magnetic stimulation (TMS). In experiments where the brain’s visual cortex has been stimulated by intense electromagnetic fields, some subjects have been found to see balls of light flying around the room; therefore it has been postulated that the stimulation of the brain by the electromagnetic activity of a thunderstorm could also create this experience. This hypothesis makes it easy to dismiss sightings of this strange happening as not valid.
But there is also some solid evidence of the reality of ball lightning. In an experiment in 2014, Chinese researchers were taking spectrographic readings of a lightning storm and serendipitously caught ball lightning on camera. They were able to do a spectrographic analysis of the ball of light and found that it was made up of silicon, iron, and calcium, and concluded that the silica had been vaporized by lightning bolts touching the earth. They measured its glow as 5 meters wide but speculated the actual size was much smaller.
However, this theory would not account for its ability to pass through windows, unless there is more than one type of ball lightning.
Ball lightning is now commonly thought to be trapped electromagnetic energy that can stay stable for a period of time and even travel. But how does this occur? There are multiple theories of what could cause this phenomenon and too many to describe in this article. But here are just a few.
A particularly popular theory is the “electrically charged solid core model,” which postulates a solid core of positive ions surrounded by a thin sheet of negatively charged electrons with a vacuum in between, producing a huge amount of electromagnetic energy. It would hold together much as the sun does, where nuclear fusion is pushing a massive amount of energy outward but the sun’s gravity is simultaneously pulling that energy back into itself.
The “microwave cavity hypothesis” says that after a lightning strike, microwave energy gets encapsulated in a nexus of electrons and can remain stable for a short period of time. This could either explode or fizzle out, and because it is pure energy, could pass right through a window.
The “spinning plasma toroid theory” has been proposed by the United States Department of Defense which claims to have produced ball lightning in their lab. It suggests that a hollow toroid of electrons creates an internal magnetic field as it moves. To get a sense of this, imagine high energy whirling in the shape of a donut.
At this point, the consensus seems to be that ball lightning is a real phenomenon that is poorly understood. But an awful lot of study has gone into trying to understand it.
Why do we care?
Aside from reassuring those people who have actually witnessed a globe of lightning that they are not crazy, simply put, if we could create a stable form of plasma, as ball lightning may represent, it could be a gateway to harnessing the power of nuclear fusion. That would provide us with a potentially enormous source of power for our communities.
Ball lightning, if it could be reproduced, controlled, and directed, could lead us forward to massive breakthroughs in clean energy production and storage.