
Though lightning flashes are fleeting, disappearing in under a second, they sometimes leave behind a permanent mark in the form of rocky formations buried underground. These structures, known as fulgurites, are often referred to as 'petrified lightning.'
In thunderstorms, the air around a lightning bolt can heat up to extreme temperatures—over 50,000⁰ Fahrenheit (27760⁰ Celsius) have been documented. To put this into perspective, the surface of the sun only reaches around 10,000⁰ F (5500⁰ C). This extreme heat often results in severe third-degree burns for those struck by lightning.
When lightning strikes a sandy beach instead of a person, a fascinating geological event can occur. The sudden, intense heat causes sand or rock particles to melt and fuse together almost instantly, giving birth to a new fulgurite.
These slender, tube-like structures have been discovered across the globe, from the vast Sahara desert to the California coastline. Composed of natural glass and typically hollow, fulgurites can grow over 13 feet long. Interestingly, Charles Darwin once noted that 30-foot-long specimens were reported in England during the 1800s.
Sadly, these glass formations are not known for their durability. Fulgurites often break down quickly due to exposure to the elements, making high-quality specimens rare. Despite this, some enthusiastic experimenters have successfully created artificial fulgurites using electrical equipment and sand. Watch this incredible video to learn how it's done: