Lightning loves travelling through plasma!
LIGHTNING PROTECTION AND HARVESTING WITH HIGH-POWER LASERS
According to researchers at the University of Arizona and University of Central Florida, high-power lasers can be used to redirect the flow of lightning.
By Sebastian Anthony @ ExtremeTech
The typical bolt of lightning carries around 5 billion joules (GJ, gigajoules) of energy, or the energy stored in 145 liters of gasoline. … Despite lightning protection systems, these strikes still cause around $1 billion in structural damage annually in the US — so there’s obviously space for improvement.
As a general rule, lightning follows the path of least resistance (impedance) to the ground. A big metal rod, with wires running into the ground, has much lower resistance than air (air has very high electrical resistance) — and so the lightning chooses the rod.
High-power lasers also don’t like to travel through air — but, when they do, they strip away electrons, leaving a wake of highly conductive ionized plasma. Lightning frickin’ loves travelling through plasma.
Continue reading …
Surrounding a laser beam with a second beam creates an energy reservoir that can sustain the central beam over long distances. This second “dress” beam helps prevent the dissipation of the primary, higher-intensity beam.
 Empire State Building pummeled by lightning [source]
 Illustration of a dressed laser filament. Courtesy of UCF College of Optics and Photonics. (via photonics.com)
 Illustration from Nature Photonics, Externally refuelled optical filaments.
[a] High-powered beam without the “dressing beam” goes only so far;
[b] high-powered beam (the “filament”) inside a low-power “dressing beam travels much farther.
 Researchers are testing a method to stimulate rain and lightning using a high-powered laser beam. (Photo : REUTERS—via Design & Trend