Researchers from the CSIRO have published a new mathematical theory which seeks to explain how and why ball lightening occurs.

 

Around the size of a grapefruit, ball lightening can last as long as 20 seconds, it has been a natural phenomenon that has long defied explanation by scientists.

 

Previous theories that have sort to explain ball lightening include microwave radiation from thunderclouds, oxidizing aerosols, nuclear energy, dark matter, antimatter and even black holes as possible causes.

 

The new theory proposes that ball lightening is caused when dense, leftover ions are swept to the ground following a lightening strike, explaining how it can occur in houses and aeroplanes.

 

Lead CSIRO scientist John Lowke proposes that ball lightning occurs in houses and aeroplanes when a stream of ions accumulates on the outside of a glass window and the resulting electric field on the other side excites air molecules to form a ball discharge. The discharge requires a driving electric field of about a million volts.

 

Lead scientist John Lowke said the any theory can only be validated if they can use it to make ball lightning in a controlled environment.

 

"Other theories have suggested ball lightning is created by slowly burning particles of silicon formed in a lightning strike, but this is flawed. One of the ball lightning observations cited in this paper occurred when there was no thunderstorm and was driven by ions from the aircraft radar operated at maximum power during a dense fog."

 

Lowke used eye-witness accounts of ball lightning by two former US Air Force pilots to verify the theory. Former US Air Force lieutenant Don Smith recalls: "After flying for about 15 minutes, there developed on the randome (radar cover) two horns of Saint Elmo's fire. It looked as if the airplane now had bull's horns...they were glowing with the blue of electricity."

 

Lowke's paper gives the first mathematical solution explaining the birth or initiation of ball lightning using standard equations for the motion of electrons and ions. He argues it is unique because it not only explains the birth of the ball but also how it can form on glass and appear to pass through glass resulting in globes of light in people's homes or in aeroplane cockpits.