A lightning strike can do something that sounds almost impossible.

It can turn sand into glass.

When lightning hits sandy ground, temperatures inside the electrical channel can become hotter than the surface of the Sun for a brief moment.

That enormous burst of energy can melt grains of sand almost instantly.

But the result isn't usually a smooth sheet of glass.

Instead, the lightning can leave behind a strange branching structure called a fulgurite.

It can look like a fragile glass tube buried beneath the ground.

And its shape can reveal something about the lightning that created it.

INTRO

Imagine a bolt of lightning striking a beach or sandy desert.

For a fraction of a second, the air around the electrical channel becomes unimaginably hot.

The surrounding sand do ...