A guided lightning bolt travels horizontally, then hits a car when it finds the lower resistance path to ground. The lightning is guided in a laser-induced plasma channel, then it deviates from the channel when it gets close to the target and has a lower-resistance path to ground. (Photo Credit: U.S. Army photo)

Scientists and engineers at Picatinny Arsenal are busy developing a device that will shoot lightning bolts down laser beams to destroy its target.

Seriously.

Soldiers and science fiction fans, you’re welcome. 

“We never got tired of the lightning bolts zapping our simulated (targets),” said George Fischer, lead scientist on the project.

The Laser-Induced Plasma Channel, or LIPC, is designed to take out targets that conduct electricity better than the air or ground that surrounds them. How did the scientists harness the seemingly random path made by lightning bolts and how does a laser help?

To understand how the technology, it helps to get a brief background on physics.

“Light travels more slowly in gases and solids than it does in a vacuum,” explained Fischer. “We typically think of the speed of light in each material as constant. There is, however, a very small additional intensity-dependent factor to its speed. In air, this factor is positive, so light slows down by a tiny fraction when the light is more intense.”

“If a laser puts out a pulse with modest energy, but the time is incredibly tiny, the power can be huge,” Fischer continued. “During the duration of the laser pulse, it can be putting out more power than a large city needs, but the pulse only lasts for two-trillionths of a second.”

Why is this important?
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