Ball Lightning is one of the strangest natural phenomenon a person can experience. Small, grapefruit-sized balls of intensely glowing light, hovering or moving silently through the air, it lasts from a few seconds to a few minutes. They are extremely rare, less than 5% of the population have seen the phenomenon – occasionally reported, but never photographed (conclusively that is).
One report of ball lightning occurred on July 10, 2001 during a powerful thunderstorm:
“A ball of light with a two-meter tail went through a window to the control room of local emergency services in Liberec, Czech Republic. The ball bounced from window to the ceiling, then to the floor and back to the ceiling, where it rolled along it for two or three meters. Then it dropped to the floor and disappeared.”
Common characteristics of ball lightning
Most reports of ball lightning include the following characteristics:
- They frequently appear almost simultaneously with cloud-to-ground lightning discharge.
- They are generally spherical or pear-shaped with fuzzy edges.
- Their diameters range from 1–100 cm, most commonly 10–20 cm.
- Their brightness corresponds to roughly that of a domestic lamp, so they can be seen clearly in daylight.
- A wide range of colors has been observed, red, orange and yellow being the most common.
- The lifetime of each event is from 1 second to over a minute with the brightness remaining fairly constant during that time.
- They tend to move, most often in a horizontal direction at a few meters per second, but may also move vertically, remain stationary or wander erratically.
- Some display an affinity for metal objects and may move along conductors such as wires or metal fences.
- Some appear within buildings passing through closed doors and windows.
- Some have appeared within metal aircraft and have entered and left without causing damage.
- The disappearance of a ball is generally rapid and may be either silent or explosive.
New theory of how ball lightning is formed
Researchers from Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO) are publishing a new mathematical theory in the Journal of Geophysical Research Atmospheres that they think explains how ball lightning is formed and why it tends to form where it does.
According to Popular Science, the researchers propose:
“Ball lightning is the result of leftover ions that accumulating and interacting with electric fields, often across some kind of dividing plane like a pane of glass (explaining why eyewitness accounts have sometimes described these glowing orbs as passing through glass.
Essentially, the paper theorizes that streams of ions–electrically charged particles–leftover from normal lightning strikes or some other source like aircraft radars (which also explains why the phenomenon has been associated with flying aircraft) accumulate on some thin planar surface like a glass window, creating an electric field on the other side. This field excites air molecules around it an in extreme cases cause a ball discharge–which can dissipate harmlessly or burst with some (terrifying) force.”