Lightening Strike?

[Hallywood78]

Found this in a video I recorded.

 

[BigAl07]

That's very cool!!

 

[MAvic_South_Oz]

A bit eerie looking too.
How many frames ?

You'd think lightning would appear bright, as it normally does, maybe this is a shadow on the lens after a strike ?
Kind of like you get when looking at lightning and get that blacked out part of vision for a while.

But then I guess you'd see the actual lightning before that then.

 

[MiniMan]

I believe he is thinking it is burnt grass, but I believe it is just water drainage....

 

[dronerdave]

That looks similar to what happens when an electrical transmission line goes down. Sometimes the voltage sprawls or spiders out seeking the best path to the substation ground and/or source. It can actually burn the wire and as the conductor melts away it leaves burn marks in the ground similar to that picture. It can turn sandy soils into glass. Hard to tell for sure, but I've seen similar voltage trails many times over the years. I've also seen lightning strikes and they do similar in turning certain soils to glass (in the industry the common term is Klinker) but it looks like a line went down from top to bottom. Lightning is more or less point orientated. Then again it might be someone burning weeds out of their field.

 

[MAvic_South_Oz]

I believe he is thinking it is burnt grass, but I believe it is just water drainage....

Ah yes, if on the ground that would probably be wet mossy kind of areas that could take on a more muddy appearance.
It has that electrical look though.

 

[dronerdave]

Ah yes, if on the ground that would probably be wet mossy kind of areas that could take on a more muddy appearance.
It has that electrical look though.

Yeah, and that view seems cropped. I'd like to see the full image. Or the video? No?

 

[Hallywood78]

Yeah, and that view seems cropped. I'd like to see the full image. Or the video? No?

It’s a screen shot from an auto generated video in DJI4Go. It’s a compilation video from the day. The original is gone. I turn left right after the shot. It’s not far from my house. I can go back when I’m home in the daylight and it’s not raining.

 

[Gindra]

Looks like a Lichtenberg Figure. I make Van de Graaf generators and am fascinated by the discharge paths etched in everything from acrylic blocks to human bodies that had been struck by lightning and lived to see another day. They look like neural pathways or the way rivers spread out in delta regions. This photo may or may not be from lightening but it does have that Lichtenberg look.

 

[sar104]

Looks like a Lichtenberg Figure. I make Van de Graaf generators and am fascinated by the discharge paths etched in everything from acrylic blocks to human bodies that had been struck by lightening and lived to see another day. They look like neural pathways or the way rivers spread out in delta regions. This photo may or may not be from lightening but it does have that Lichtenberg look.

It does, but the kind of large currents required to affect the ground like that don't travel on the surface during lightning strikes.

 

[Gindra]

It does, but the kind of large currents required to affect the ground like that don't travel on the surface during lightning strikes.

Yes, normally that is the case. However, depending on the variables of soil composition and moisture content, surface scaring can occur. Here's a link to a story about a lightening strike at a golf course and the figure etched into the green.

Lightning strike on Rookery golf green creates Lichtenberg figure

 

[sar104]

Yes, normally that is the case. However, depending on the variables of soil composition and moisture content, surface scaring can occur. Here's a link to a story about a lightening strike at a golf course and the figure etched into the green.

Lightning strike on Rookery golf green creates Lichtenberg figure

Interesting - I've not seen that before. That must be a result of a layer of dry, low-conductivity material below a conducting surface layer. It's pretty localized though.

 

[Gindra]

Interesting - I've not seen that before. That must be a result of a layer of dry, low-conductivity material below a conducting surface layer. It's pretty localized though.

Yes, and the other variable is how much plasma accumulated on the ground prior to the strike. Plasma being super conductive. It can pool up just like water, forming a shallow pond on the surface.

 

[Prismatic]

For the record, there's quite a difference between "lightning" and "lightening"!

 

[Gindra]

For the record, there's quite a difference between "lightning" and "lightening"!

Yep! Quite a difference!! Whoops.

 

[sar104]

Yes, and the other variable is how much plasma accumulated on the ground prior to the strike. Plasma being super conductive. It can pool up just like water, forming a shallow pond on the surface.

Not sure about that. Plasma is not a stable form of matter under ambient conditions, and requires magnetic containment - it can't just sit around like a regular gas.

 

[Gindra]

Not sure about that. Plasma is not a stable form of matter under ambient conditions, and requires magnetic containment - it can't just sit around like a regular gas.

That is true. Plasma normally behaves like a gas and needs a container to keep it from dispersing.

The container that holds lightning-generated plasma is the field of electrical energy that develops between the thundercloud and earth's surface. The separation of charge that exists begins to disassemble air molecules, creating the ionized 'gas' known as plasma. When this is strong enough to be seen, it had been called St.Elmo's Fire and was often seen on the tips of sailing ship masts and church steeples.

While pointed objects are best for concentrating the charges necessary for the creation of plasma, the step leaders that extend from the cloud to the ground (precursors to the lightning bolt) will find all kinds of places to "land". Sometimes a tree. Or a steeple. And sometimes the surface of the earth. Whatever offers the least path of resistance.

As the separation of charge gets stronger it creates something akin to a tunnel between the cloud and the terminus point on the ground. It the early stages of this, a person can feel the prickly presence of static electricity. There may be crackling sounds and tiny coronal discharges in the area. If the conditions are right and the separation of charge is strong enough, the blue-purple plasma (ionized oxygen and nitrogen) becomes visible and pools around the terminus points.

It is the tunnel created by the separation of charges that holds these “pools” in place. Not for long, of course! The step-leaders complete the circuit and the lightning bolt follows that path. And when the circuit is completed, there is no more separation of charge! No more plasma. Just a lingering smell of ozone.

I replicate this process with Van der Graaf generators. As long as I keep the terminals far enough apart to keep the “lightning bolt” from discharging, but close enough to create a field of ionized energy, a visible shaft of this blue-purple plasma develops and will stay there as long as I don’t let discharge occur.

 

[sar104]

That is true. Plasma normally behaves like a gas and needs a container to keep it from dispersing.

The container that holds lightning-generated plasma is the field of electrical energy that develops between the thundercloud and earth's surface. The separation of charge that exists begins to disassemble air molecules, creating the ionized 'gas' known as plasma. When this is strong enough to be seen, it had been called St.Elmo's Fire and was often seen on the tips of sailing ship masts and church steeples.

While pointed objects are best for concentrating the charges necessary for the creation of plasma, the step leaders that extend from the cloud to the ground (precursors to the lightning bolt) will find all kinds of places to "land". Sometimes a tree. Or a steeple. And sometimes the surface of the earth. Whatever offers the least path of resistance.

As the separation of charge gets stronger it creates something akin to a tunnel between the cloud and the terminus point on the ground. It the early stages of this, a person can feel the prickly presence of static electricity. There may be crackling sounds and tiny coronal discharges in the area. If the conditions are right and the separation of charge is strong enough, the blue-purple plasma (ionized oxygen and nitrogen) becomes visible and pools around the terminus points.

It is the tunnel created by the separation of charges that holds these “pools” in place. Not for long, of course! The step-leaders complete the circuit and the lightning bolt follows that path. And when the circuit is completed, there is no more separation of charge! No more plasma. Just a lingering smell of ozone.

I replicate this process with Van der Graaf generators. As long as I keep the terminals far enough apart to keep the “lightning bolt” from discharging, but close enough to create a field of ionized energy, a visible shaft of this blue-purple plasma develops and will stay there as long as I don’t let discharge occur.

In the Van der Graaf example you are continually ionizing the gas. If you turn off the potential difference then that region of ionized gas will vanish immediately.

 

[WithTheBirds]

For the record, there's quite a difference between "lightning" and "lightening"!

No difference for those of us who automatically guessed what was meant (given the context) and just moved on. Predictive text and auto correct in our current world make this guessing routine a necessity. Unless we may want to be bogged down by trivial details.

 

[Gindra]

In the Van der Graaf example you are continually ionizing the gas. If you turn off the potential difference then that region of ionized gas will vanish immediately.

Exactly. I've done experiments with a shaft of that plasma, seeing how it responded to magnetism. (It does). Once that VDG is turned off, or once the electrode discharges, the plasma is gone.

Here's a Scientific American article about St. Elmo's fire. The paragraph that suggests the presence of plasma at ground level prior to a lightning strike is:

'St. Elmo's fire is seen during thunderstorms when the ground below the storm is electrically charged, and there is high voltage in the air between the cloud and the ground. The voltage tears apart the air molecules and the gas begins to glow. It takes about 30,000 volts per centimeter of space to start a St. Elmo's fire (although sharp points can trigger it at somewhat lower voltage levels.)"

"What causes the strange glow known as St. Elmo's Fire? Is this phenomenon related to ball lightning?"

www.scientificamerican.com

This phenomenon has been reported throughout history. But it is an ephemeral phenomenon for just the reason you gave. The plasma tunnel or channel that precedes and accompanies the lightning strike is only observable for the briefest moment but is most observable at the top and bottom of the channel. Its existence is dependent upon the continued potential difference as with the VDG. Very rare for a slowly developing potential difference to intensify enough to produce these effects and rarer still for them to last long enough to be observed.
This discussion has drifted way off-topic. My fault entirely. I'm a true nerd when it comes to certain things. Don't get me talking about building crystal radios!

Thanks for engaging with me Sar104.