Lighning may be startedby cosmic rays

[tom baker]

Last week there as a PBS Nova broadcast with a segment on lighting.
The experts are not sure what starts lighting discharges. The lastest theory is cosmic rays. They can't explaing lighting with the cloud to cloud theory. The show also included an interview with at the Flordia lightning reseach center where they shoot rockets into the sky with wires to attrach lightning.
Heres a link to watch the 9 min segment.
http://www.pbs.org/wgbh/nova/sciencenow/3214/02.html

 

[Physis 2]

Re: Lighning may be startedby cosmic rays

Hi Tom.

I'm not surprised Nova can't explain it. I thought we had a pretty solid idea of where lightning comes from. I guess not.

 

[bphgravity]

Re: Lighning may be startedby cosmic rays

I've been to the University of Florida lightning research center in Gainsville to watch rocket initiated lightning. The rocket basically carries an upwards streamer that may interact with a stepped leader heading down. If the short is made, the flash stroke completes.

I don't see how cosmic rays would play any part. Unless it is the componet that starts the leader downwards from the cloud.

This stuff is quite interesting, however I think the really important research is what happens when structures and other equipment become apart of the return stroke path.

The recent newsletter from Mike discussed some interesting research performed on this topic. I have not had the time to read the entire site, but look forward to it soon.

 

[pierre]

Re: Lighning may be startedby cosmic rays

The study of lightning is sort of at the same point in time as when us humans discovered the earth was not flat, but indeed round - are we really sure it is round? .

So this "cosmic" thing they are alluding to just may in fact be true, although the facts may take years to actually become fact or fiction.
I will say I find it very interesting though. The URL that Tom has provided also has links to other Lightning sites which are also very interesting.

 

[LarryFine]

Re: Lighning may be startedby cosmic rays

I recently watched a show on one of the "really learn something" channels, and they talked about a recently-discovered phenomenon known as "sprites", which were streaks of discharge emerging upward from clouds that were discharging lighning to the ground.

See more here": http://www.fma-research.com/spriteres.htm

 

[Physis 2]

Re: Lighning may be startedby cosmic rays

That's certainly a pretty cool graphic Larry!

[ October 25, 2005, 01:17 PM: Message edited by: Physis 2 ]

 

[bphgravity]

Re: Lighning may be startedby cosmic rays

The NASA guys sure get alot of neat video and pictures of all kinds of strange electrical phenomenon during shuttle and rocket launches. I beleive NASA has been working on electrical tethers to extend out which pass through earth's magnetic field and can produce enough current to charge shuttle systems.

I think during one experiment, they actually blew up some equipment from a surge of some kind.

 

[Physis 2]

Re: Lighning may be startedby cosmic rays

Sounds cool, got a link?

 

[steve66]

Re: Lighning may be startedby cosmic rays

I think during one experiment, they actually blew up some equipment from a surge of some kind

I vaugely remember that too. They had some piece of wire that was incredibly long (measured in miles, I think) that they unrolled from the shuttle.

Steve

 

[steve66]

Re: Lighning may be startedby cosmic rays

I found this with a quick search:

Nasa STS-75

 

[bthielen]

Re: Lighning may be startedby cosmic rays

I saw the NOVA program as well. The one thing that seems to have been missed is this. They did not say that cosmic rays caused the lightning. What they did say is that based on test data they were unable to explain how lightning was able start because the voltage potential was not great enough to cause the lightning to jump the distances that it does. Their theory is that the cosmic rays provide the catalyst for ignition. As if their passing through breaks down resistance between the opposing forces and provides a path for the lightning to follow. The rockets being sent up do a similar thing by dragging the wire. The wire provides a lower resistance path for the lightning to follow.

Bob

 

[steve66]

Re: Lighning may be startedby cosmic rays

There was even some speculation that this is what caused the last shuttle disaster. One photo showed what appeared to be a bolt of lightning intercepting the shuttles path. But NASA claims this was actually a vibration of the camera.

Steve

 

[Physis 2]

Re: Lighning may be startedby cosmic rays

I wonder if friction is causing static charges?

They might be going too fast.