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Laser brings a bolt of discovery with lightning 'precursor'

 HIGH-POWERED LASER TAKES AIM AT THE CLOUDS

By Doyle Rice, USA TODAY
For the first time, a high-powered laser has been used to trigger electrical activity within a thunderstorm.

"This was an important first step toward triggering lightning strikes with laser beams," says lead researcher Jérôme Kasparian of the University of Lyon in France. Although the researchers weren't able to create a lightning strike, "it was the first time we generated lightning precursors in a thundercloud."

The study was published last week in the online journal Optics Express.

ORIGINAL SOURCE: Optics Express article (PDF)

The laser worked by emitting a high-powered directional beam of light with enough energy to strip electrons off atoms, the same way that electrical fields within thunderclouds do. Natural lightning is created when those negatively charged electrons connect with positive electrical charges from the ground, generating a powerful electrical current we see as lightning.

Artificially triggered lightning strikes allow researchers to study how and why lightning forms, and also give engineers a way to evaluate and test the lightning sensitivity of airplanes and infrastructure, such as power lines.

The research was conducted at the New Mexico Institute of Mining and Technology's Langmuir Laboratory at 10,500-foot South Baldy Peak, N.M., during two thunderstorms in September 2004.

Researchers were sure the laser caused the electrical activity because "we observed that some minor electric events were synchronized with the laser, precisely at the position where the laser beam was emitted," Kasparian says. The events included the phenomenon known as "St. Elmo's Fire," a bluish glow of light associated with thunderstorms.

"The long-term objective is to use this laser-induced electrical activity to 'channel' or 'seed' a lightning strike in a controlled way so that lightning strikes where you want it to, rather than just randomly," says John Dudley of the University of Franche-Comté in France, an editor with the Optics Express journal.

Triggering lightning strikes isn't new: Scientists have done it since the 1970s by shooting small rockets into clouds, which spool wires connected to the ground. Typically, however, only about 50% of rocket launches actually trigger lightning.

Though the idea behind using lasers to trigger lightning has been around for more than 30 years, previous lasers hadn't been powerful enough. The more powerful lasers, such as the one developed by Kasparian's team, may change that.

Scientists say laser technology should make triggering lightning strikes quicker, more efficient and cheaper, and it should open more applications. Kasparian adds that the next-generation laser from his team should be able to trigger an actual lightning strike, because the laser will be 10 times more powerful than the one in the 2004 experiment.

The project was initiated by the National Center for Scientific Research in France and the German Research Foundation.

This would actually be kinda neat Bill, if it lead to a system that could trigger a strike when it sensed the potential building in a cloud. Maybe cities prone to strikes (like Tampa) could one day have a set up that directs the strikes to a certain spot, and somehow harness or store the energy.

Of course, the first time they 'miss' and someone's house gets zorched, well... 

That whole thing about messing with Mother Nature comes to mind.  :)

Yeah Todd, I have always dreamed of connecting a tall piece of wire in the air with a room-sized capacitor...

Not sure if anyone has seen this and I can't remember if it was a science channel or weather channel but there was  a weather researcher who was studying lightning.  The way he would induce a lightning strike during a storm was to launch essentially model rockets with a wire attached.  There was video footage of such an event and when I was watching it I thought that was kinda cool yet nuts. 

Yeah, I saw that - would vaporize the wire but left a nice image of the bolt on the screen where it followed the wire to ground.

Bill, I dunno about that giant cap-in-the-house approach. If you think a puked electrolytic makes a mess.... and loud?  ;)

Folks are finding ways to harness the movement of the oceans for energy, so eventually they should get around to capturing lightning. Just not in a bottle.

Bob,
I also saw the rocket thing. That is a lot of energy to try to store. HMMMM thats one big PDM filter. This sounds like a good story line for a bugs bunny cartoon. Shoot your laser pen at a cloud and down comes a bolt to cook you.

Scitentific American article "the amateur scientist" October, 1974 shows how to make electrostatic motors that run off the 'free' electric charge of the earth's atmosphere. I think one of the motors is 1/10 hp.

"Experiments Which Show That the Earth Functions As an Electrostatic Machine" Scitentific American article by C. L. Stong May, 1957,  refers to a ham radio operator: "ONE SUNNY MORNING last fall a jolt of electricity knocked Fred Ellis, an Ohio radio ham, from the roof of his barn. Fortunately Ellis landed on a stack of straw and lived to tell the tale. "I started to hook a ground wire to a 50-foot antenna tower on the roof," he writes, "when a fat spark jumped from the metal tower to my hand and knocked me off balance. " The picture is from that article. I believe this is entirely "fair use".
 

When I was a punk back in Illinois, I connected a Simpson 260 milliampmeter between a 1,200' long wire antenna and ground.

During fair WX days, there was always a constant DC current that could be observed, but not of consistent polarity. Not very much, either. Just a few 10s of microamps. Same for stormy days, except the needle would violently slam either direction. Part of any such project would probably require the use of a diode array.

I need to revisit that experiment some day.

They launch the small rockets into storms from the Langmuir lightning research lab S. of Socorro, NM too. My neighbor has worked there and witnessed the experiment.

I remember when, as a teen, I saw the pine tree that my 40m dipole was attached to take a direct hit in SC. It was LOUD. The dipole and RG58 melted, lucky I didn't have my HW16 connected that day. The coax came inside and was sitting on the floor. A big flash spark jumped between the PL259 and the nearby AC outlet as it sought ground. It burned the staples under the floor all the way back to the breaker panel, where the breaker was permanently tripped.

I still fear lightning when it starts popping around me.