Ordinary lightning is over in a fraction of a second: a jagged flash, a crack of thunder, darkness again. Ball lightning, if the reports are to be believed, is something else — a glowing sphere that drifts through the air during a thunderstorm, lingers for seconds, and then disappears, sometimes quietly and sometimes with a bang. People have reported it for centuries, yet science still cannot say, with confidence, what it is — or even, definitively, that it exists.
That uncertainty is the story: ball lightning sits at the edge of atmospheric science, where observation, folklore, and laboratory experiment meet and do not quite agree.
What witnesses describe
The reports, collected over hundreds of years, are consistent in outline and inconsistent in detail. A typical account describes a luminous, roughly spherical object, most often grapefruit- to basketball-sized, though reports range from pea-sized to several metres across, usually red, orange, or yellow. It appears during or just after a thunderstorm, floats a little above the ground, and lasts a few seconds — far longer than an ordinary lightning flash.
Witnesses say it can move horizontally, hover, or roll along a surface, and is often said to pass through windows or walls, drift down a chimney, or cross a room before disappearing. A hissing sound is sometimes reported, and a smell of ozone or burning sulphur is said to linger. Some accounts say the ball explodes loudly; others say it vanishes silently.
That consistency is why the phenomenon has been taken seriously; the inconsistency is why it has not been explained.
Accounts from history
Descriptions of glowing balls in storms go back centuries. On 21 October 1638, during the Great Thunderstorm at Widecombe-in-the-Moor in Devon, England, a “great ball of fire” was reported to have come through a church window during a service, in a storm that damaged the building and killed four people — a contemporary description by frightened witnesses, not a scientific measurement.
In 1753, the physicist Georg Richmann died in St Petersburg while experimenting with lightning during a thunderstorm. Later accounts linked his death to ball lightning, describing a glowing ball that struck him. His death during an electrical experiment is documented; that a ball of lightning caused it is a later interpretation, and it is disputed.
Tsar Nicholas II is said to have described seeing ball lightning, and the writer Laura Ingalls Wilder described glowing balls her family saw during a storm on the prairie, which her mother chased away with a broom. Vivid accounts — and, by scientific standards, anecdotes. They establish that people believed they saw something, not what it was.
One survey-based estimate suggests about 5 per cent of the Earth’s population has seen ball lightning, and another analysis examined some 10,000 reported cases — survey results, not measurements, depending entirely on what people say they saw.
The one observation scientists keep returning to
For most of its history, ball lightning had no instrument record at all. That changed, at least partly, in 2012.
Researchers from Northwest Normal University in Lanzhou, China, were studying a thunderstorm with video cameras and spectrometers when, by chance, they recorded an event just after a lightning strike. A glowing ball appeared, travelled horizontally for about 10 metres, and lasted a few seconds. The spectrometer detected silicon, iron, and calcium — elements also present in the local soil. The observation was published in January 2014, with a video and an optical spectrum.
It is the best-documented natural case in the literature, and the closest thing to a measurement that exists — but a single event cannot settle a phenomenon. It supports one idea, that a lightning strike can vaporise soil and form a glowing ball, without proving that all reported ball lightning works that way.
Plainly: no photograph claimed to show ball lightning has been universally accepted as genuine, and many images online are mislabelled pictures of ordinary lightning or lens effects. The image chosen for this article shows ordinary lightning, not a confirmed ball-lightning event — because no such confirmed photograph exists.
The theories
Scientists have proposed many hypotheses, and none has been confirmed. The main ones are:
Vaporised silicon. A lightning strike heats soil, vaporising silicon and other minerals. The vapour condenses into tiny particles that oxidise in the air, releasing light and heat as a glowing, buoyant ball. This is the explanation the Lanzhou observation most often supports, since the spectrum matched the local soil — but it does not explain reports of balls over water or far from the ground.
Microwave cavity. When lightning strikes the ground, it can produce microwave radiation that becomes trapped inside a bubble of plasma — ionised gas — which then drifts through the air. This idea, developed in a 2016 study, would explain the ball’s movement and lifetime, but remains a theoretical model, not a demonstrated mechanism.
Plasma and charged particles. Several models treat the ball as plasma held together by electrical or magnetic forces, or as a spinning ring of plasma. Laboratory experiments have produced glowing plasma balls, but laboratory conditions differ greatly from a thunderstorm, and it is unclear how these relate to the reported phenomenon.
There is also a more sceptical idea, from at least one study, that about half of all ball lightning sightings are hallucinations caused by magnetic fields generated during storms. That claim is itself disputed, and does not account for the Lanzhou recording or for reports by multiple witnesses — a reminder that eyewitness testimony during a frightening storm is not a laboratory instrument.
Laboratory work has produced lookalikes: in 2006, researchers at Tel Aviv University created a laboratory version using a microwave beam, and home experiments with microwave ovens and a lit match can produce small, rising glowing balls of plasma. Visually similar to the reports — but how they relate to the supposed natural phenomenon remains unclear. A lookalike is not a proof.
What the evidence says
- Documented: People have reported glowing, spherical objects during thunderstorms for centuries, most often grapefruit- to basketball-sized, red, orange, or yellow, lasting a few seconds and moving horizontally or hovering.
- Documented: In 2012, researchers in Lanzhou, China, recorded a glowing ball on video and with a spectrometer after a lightning strike. It travelled about 10 metres horizontally, and its spectrum showed silicon, iron, and calcium, matching the local soil. The observation was published in 2014.
- Documented: Laboratory experiments, including a 2006 microwave experiment at Tel Aviv University, have produced glowing plasma balls similar to the reports.
- Disputed: Whether ball lightning exists as a single physical phenomenon at all. Scientific data remain scarce and there is no reproducible observation, so its existence as a distinct phenomenon remains unproven, and some scientists doubt it.
- Unproven: Every proposed explanation — vaporised silicon, microwave cavities, plasma models, and the rest. None has been confirmed.
- Claimed, not proven: The historical accounts, including Widecombe-in-the-Moor in 1638, the death of Georg Richmann in 1753, and the sightings attributed to Tsar Nicholas II — reports, not measurements.
What remains unknown
Almost everything. Ball lightning may be one phenomenon or several: a real, rare product of lightning striking the ground, as the Lanzhou observation suggests; a trick of perception during storms; or a mixture of real events and misremembered ones. What is missing is what science needs most — a second, third, and tenth instrument-recorded event that can be studied and reproduced.