Cloud to Ground Lightning

Bolts of lightning descend like tentacles from a storm-roiled sky. It was Benjamin Franklin who discovered in 1752 that lightning is actually electricity. In his now-famous experiment, he sent a kite with a metal key tied to the string up into a thunderstorm. When he saw sparks leap from the key, his hunch about lightning was confirmed.

Lightning strikes the ground near a dirt road somewhere in rural United States. Lightning occurs about 1.4 billion times per year, with about 20 million bolts hitting the Earth's surface.

Lightning cuts a jagged line through the evening sky in Montana's Bighorn Canyon National Recreation Area. Lightning bolts symbolizes things like power, swiftness, fire, or God's punishment in many cultures, including Norse, Roman, and Native American.

A tangle of lightning, including multiple ground strikes, crackles in the Montana sky. At any given time, some 2,000 thunderstorms worldwide produce lightning that strikes the Earth about 100 times every second.

Whips of lightning crack the sky near rural Walton, Nebraska. Because a flash of lightning is actually multiple strokes that occur in a fraction of a second, time exposure photographs like this best capture these rapid-fire displays.

Threads of lightning illuminate Amman, Jordan's nighttime cityscape. Lightning is a discharge of electricity that occurs when excess electrical charges build up in clouds.

A saguaro cactus stands tall amid a frenzy of lightning bolts in Arizona. During thunderstorms in parts of the western United States, rain often evaporates before hitting the ground, making the region vulnerable to brush fires from lightning hitting the dry earth.

Lightning bolts flare in all directions over an open plain. Cloud-to-cloud bursts, among the more rare forms of lightning, are nicknamed crawlers because they appear to crawl across the sky.

A dramatic cloudburst releases jagged bolts of lightning deep into the Grand Canyon near Point Sublime.

A triple-strike of cloud-to-ground lightning connects saturated skies with arid sand in North Carolina's Jockey's Ridge State Park.