After centuries of guesswork and speculation scientists believe they have an explanation for the phenomenon of ball lightning.
Scientists from Northwestern Normal University in China were collecting data on a thunderstorm in 2012 when a lightning bolt struck the ground near their instruments. A glowing ball of light five meters wide traveled about 15 meters before disappearing.
According to an account published today in the journal NewScientist and a paper (below) published this week in Physical Review Letters, a spectrograph showed that the ball of light was made of silicon, iron and calcium, which are the same materials that make up dirt.
That supports a theory developed in 2000 by John Abrahamson of the University of Canterbury in New Zealand, who theorized that the heat from lightning vaporizes silicon oxide, a blast wave blows the gas into the air and it's ignited as it re-oxidizes because of carbon in the soil.
"Here's an observation which has all the hallmarks of our theory,” Abrahamson told NewScientist. “This is gold dust as far as confirmation goes."
Read the paper on the phenomenon recorded in China: