Experts From UF Dig Up World’s Longest Solidified Lightning Bolt

Published: May 19 1997

Category:Engineering, Florida, Research, Sciences

GAINESVILLE — When researchers from the University of Florida began digging into the ground where a lightning bolt had hit, they thought it would be just another minor excavation.

But the longer they worked, digging along the glassy path left behind by the dirt-melting lightning, the more apparent it became that this was no ordinary dig. What they finally unearthed was verified recently by the Guinness Book of Records as the world’s longest fulgurite ever excavated.

“There isn’t much known about fulgurites,” said Martin Uman, chairman of UF’s electrical and computer engineering department and a member of the research team. “It’s very exciting for us to have been able to find this one. But I’m sure there are longer ones out there waiting to be discovered.”

The record-breaking fulgurite includes two branches, one almost 16 feet long and the other reaching 17 feet.

This will mark the first time Guinness includes the fulgurite category in its data base of records. Guinness spent six weeks researching the topic until it confirmed that the UF discovery is the longest on record. The closest is a 13-foot fulgurite currently housed in a museum.

Uman and his team began excavating last summer after a bolt struck the ground at Camp Blanding, near Starke, where UF maintains a lightning research facility by agreement with the U.S. Army National Guard.

“This strike kicked up a lot of dirt and made some fire,” Uman said. “Observers as well as surveillance cameras spotted the lightning, and a flag was placed in the ground on the burn mark.”

Fulgurites have been described by some as solidified lightning bolts. They are glassy tubes that lightning forms below the ground as it tears through the soil. The lightning melts the sand, which solidifies again when it cools to form the hollow glassy material.

Daniel Cordier, formerly of UF’s geology department, supervised the excavation and did most of the digging and removal of the fulgurite.

“If a normal citizen tries to dig one of these out of the ground,” Uman said, “they would destroy it because fulgurites are so fragile. It takes experts who are skilled in working with special tools and are used to digging up fossil bones. It’s definitely an art.”

UF’s facility at Camp Blanding was established in an effort to understand lightning and how it affects electrical power sources. The research has shown that underground power systems can be struck by lightning because the strike keeps moving below the surface.

Uman said the fulgurite, intact with its two branches, probably will go to a museum. Several have expressed an interest, but the location must be large enough to appropriately display it in its original form, he said.

Although the lightning facility was not intended for fulgurite research, Uman said interest in the underground lightning bolts has grown during the last few years.

“We have dug up a lot of fulgurites,” said Uman. “A rather large one of ours is now on display at the Electric Power Research Institute in Palo Alto, Calif.”

A 10-foot fulgurite is being prepared for display in the lobby of UF’s new engineering building. Uman said the team will continue looking for record-breaking fulgurites.

“We’ll keep looking for a longer one,” Uman said. “We may keep digging these things up forever. It’s fun.”



Karen Meisenheimer

Category:Engineering, Florida, Research, Sciences