Chinese scientists are first to probe rare ball lightning phenomenon

A group of Chinese scientists may have scored a first when they managed to make detailed observations of a ball of lightning.

 

The work of Jianyong Cen, Ping Yuan and Simin Xue – who observed a great ball of lightning in China in 2012 - was published only last Jan. 17 in the "Physical Review Letters."

 

"Ball lightning (BL) has been observed with two slitless spectrographs at a distance of 0.9 km. The BL is generated by a cloud-to-ground lightning strike. It moves horizontally during the luminous duration," they said in their abstract. 

 

Also, they reported the evolution of size, color, and light intensity in detail.

 

"The spectral analysis indicates that the radiation from soil elements is present for the entire lifetime of the BL," they said.

 

The three scientists are with the College of Physics and Electronic Engineering at the Northwest Normal University in Lanzhou, Gansu in China.

 

A separate article on NewScientist.com said the ball lightning phenomenon is difficult to study since the balls are unpredictable and last for a few seconds.

 

It added previous explanations for this "ranged from electrically charged meteorites to hallucinations induced by magnetism during storms." 

 

But in 2012, Cen and his colleagues managed to observe the ball lightning with video cameras and spectrographs, "purely by chance."

 

"When a bolt struck the ground, a glowing ball about five meters wide rose up and travelled about 15 meters, disappearing after 1.6 seconds," it said.

 

NewScientist said the spectrograph readings showed the main elements in the ball were the same as those found in the soil: silicon, iron and calcium.

 

"The observations support a theory for making ball lightning put forth in 2000 by John Abrahamson at the University of Canterbury in New Zealand," it added.

 

Abrahamson had theorized that when lightning hits the ground, the sudden, intense heat can vaporize silicon oxide in the dirt, and a shock wave can blow gas up into the air.

 

If the soil has carbon such as from in dead leaves or tree roots, it can steal oxygen from the silicon oxide, leaving silicon vapor. The hot ball of gas is quickly reoxidized due to Earth's oxygen-rich atmosphere, "and this reaction makes the orb glow briefly," NewScientist said.

 

While when scientists at Tel Aviv University in Israel created ball lightning in the lab in 2006 by firing mock lightning at sheets of silicon oxide, what happened China was the "first time such an orb has been captured in nature with scientific instruments," it added. — KDM, GMA News