Great balls of fire! Ball lightning exists.

Q: I was wondering if Ball Lightning exists. What do you know about it? Where does it happen? When and why? (Chris, San Diego, California)

A:  Ball lightning exists. Five percent of the world’s population (statistical analysis reported in the plasma physics division of the American Physical Society) has seen the phenomenon although many are reluctant to say so because it sounds so bizarre. Five percent’s about the same percentage that has seen ordinary lightning strike close by. Reports of ball-lightning sightings go back to the ancient Greeks. We cannot explain the phenomenon yet, though we have theories galore.

Lightning balls usually form during thunderstorms and right after a lightning strike. [C. Clark, NOAA National Severe Storms Laboratory]

Here’s one account by Terry Stetler who saw ball lightning in the summer of 1966 on a produce farm where he grew up about 30 miles southwest of Detroit, Michigan.

He and his dad were standing on the back porch of their farmhouse watching lightning strike all around. Suddenly, an enormous bolt hit a walnut tree in the middle of their soybean field.

"Almost immediately several bluish-white glowing balls (about soccer-ball size) emerged from under the tree and floated in random directions. Three came towards our house at a height of six to eight feet off the ground.

"The first hit a wellhead in the barnyard and exploded with a noise like a transformer burning out. The second struck the base of our windmill and expired with a crackle." No damage, not even a scorch mark.

The third ball meandered around until it got about fifteen feet from the house. "It drifted left, right, and back. Then it started to grow larger (about beach-ball size) whereupon it made a fizzing sound and disappeared."

That’s a typical sighting but ball lightning varies wildly.

Plasma ball generated in the laboratory to investigate ball lightning — lasted 0.16 seconds. [© 2001 - 2003, Sergei Emelin and Alexei Pirozerski, used by permission, http://balllightning.narod.ru  ]

What we know about it.

It’s a ball of light (orange, red, yellow, blue, or other colors) that slowly drifts parallel to and a few yards (meters) above the ground, sometimes apparently unaffected by breeze or wind. Often it spins as it moves. Sometimes it bounces off the ground or other solid objects. Observers see the light spheres clearly in the daytime —about as bright as a 25 to 100 watt incandescent light bulb. The balls, usually grapefruit size, can be as small as a pea or as large as a beach ball. They last an average of 25 seconds — from a few seconds long up to several minutes.

The spheres demonstrate little heat normally although they have been known to burn barns, boil a tub of water, penetrate flesh, char limbs, and kill people.

When does it happen?

During a thunderstorm, usually immediately after a lightning strike. Sometimes, though, they occur near the ground without a lightning discharge.

Where?

Almost anywhere. After a lightning strike, balls can suddenly appear out of the ground as they did for Terry Stetler. Sometimes they descend from clouds or hang in the sky. Within seconds after an Eastern Airlines jet was hit by lightning, a glowing sphere emerged from the pilot’s cabin, floated down the aisle, and vanished near the rear lavatory. A fiery sphere burned a basketball-size hole in a screen door, entered an Oregon house, descended to the basement, and wrecked an old upright ironing machine.

Why does it happen?

We don’t know. Although theories number in the hundreds, none is generally accepted. So far, even the best theories only explain some aspects of ball lightning — but not all. The theories propose various causes of ball lightning:

• an atmospheric maser
• a stable plasma ball
• a standing wave of electromagnetic radiation
• an electrical discharge similar to corona discharge
• a vortex
• a suspension of fine particles in the air (an aerosol) that interact
  Click here for why lightning balls happen — according to John Abrahamson’s aerosol-morphed-into-lightning-ball theory.

Goodness gracious, great balls of fire — Jerry Lee Lewis

Update:  Ball lightning apparently is created whenever lightning strikes silicon in soil.  We have created such lightning in the lab.  Could these be the right balls of fire? Newswise, Jan. 11, 2007

Further Reading:

Blue jet:  One night I was watching a storm and the lightning turned blue. How did that happen?
Cause:  What causes lightning?
Heat:  Lighting is supposed be three times hotter than the sun. Since the lighting flashes are closer than the sun how come we don’t feel the heat when it flashes?
How wide & long:  My kids were wondering how wide and long lighting can be.
MountEverest: Does lightning strike Mount Everest?
Ocean strikes:  If lightning strikes the ocean, do the marine animals get hurt or killed?
Where it hits:  Where in the world do the most lightning strikes occur?

Sci.Geo.Meteorology Newsgroup: Ball lightning information by Michel T. Talbot

Sergei Emelin and Alexei Pirozerski: Ball lightning and metastable substance

Peter F. Coleman:  Great Balls of Fire --- a unified theory

Science Hobbyist: Ball lightning page by Bill Beaty

Science News: Anatomy of a lightning ball by Peter Weiss

Scientific American: Ball lightning by Chris Sparrow

Science Hobbyist: Ball lightning reports (including Terry Stetler’s)

Join the conversation.  Leave a comment!

(Answered July 30, 2004, updated Sep. 29, 2007)