Scientists capture mysterious gigantic lightning flashes

Rarely seen or photographed supercharged lightning flashes into outer space.

Gigantic jet/Duke University
University scientists have captured a picture of huge blasts of lightning known as gigantic jets that can shoot upwards over 40 miles from thunderstorms.

 Video showing the gigantic jet.

Scientists at Duke University in North Carolina said the rarely seen and even more rarely photographed -- images of gigantic jets have only been recorded on five occasions since 2001-can flash up to the lower levels of space, or ionosphere and are substantially larger than their downward striking cousins.

Gigantic jets travel farther and faster than conventional lightning because thinner air between the clouds and ionosphere provides less resistance. Whereas a conventional lightning bolt follows a six-inch channel and travels about 4.5 miles down to earth, the gigantic jet recorded by the scientists contained multiple channels and traveled about 40 miles upward, researchers stated.

"Gigantic jets are literally lightning that comes out of the thunderclouds, but instead of going down, like most lightning strokes do, these apparently find their way out the tops of thunderclouds, and then keep going and keep going and keep going until they run into something that stops them," said study leader Steven Cummer, an electrical and computer engineer at Duke University in North Carolina. "Our measurements show that gigantic jets are capable of transferring a substantial electrical charge to the lower ionosphere."

The Duke University team caught a one-second view and magnetic field measurements that are now giving scientists a much clearer understanding of these rare events.

Scientists don't know what conditions or what types of storms are conducive to gigantic jet formation. It has been difficult in the past to obtain images of gigantic jets because they occur so quickly that cameras have to be trained on them at the precise moment they occur, researchers stated.

According to researchers, gigantic jets were discovered in 1992 by Dr. Victor Pasko in Puerto Rico, and since then only 12 jets have been photographed over land.

When it comes to lightning, most people see it and head for safety, choosing not to stop and discuss what type it is. But researchers recently said they have developed a technique that shows how diverse lightning can be.

For example, most people don't see lightning see lightning strikes that go from clouds to the ground, but some lightning goes upward, forming blue jets and gigantic jets. Perhaps the most dangerous lightning appears as "bolts from the blue" - lightning that begins upward, but then moves sideways and then downward to hit the ground as much as three miles from a thunderstorm, say researchers at New Mexico Tech and Penn State.

About 90% of lightning occurs inside clouds and is not visible to the casual observer, researchers said. The researchers wondered if lightning that appears within clouds and the lightning that escapes upward or downward shared the same development mechanisms, researchers said. Lightning forms in clouds when different areas of the cloud become either positively or negatively charged. Once the electric field near a charged area exceeds a certain propagation level, lightning occurs. The type of lightning depends on where the charge builds and where the imbalance in charge exists in the clouds. The mechanism behind different types of lightning is what the new model shows, researchers said.

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