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vortexring

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No, you're right Max.:)
Jack, it can sometimes be visible to the naked eye, but if you're close enough to see it, you're also close enough to see the light emitting from the a/c's internal instruments! Coupled with the noise...

A similiar effect can be seen if you go into your garage with a sugar cube and a hammer. Ensuring it's properly dark, and your eyes have adjusted (and you can remember where you've placed the sugar cube), smash it hard with the hammer and see what happens. Now, imagine wearing an image intensifier and consider how much brighter the effect would be.
Then explain to the missus what on earth you're up to. . .:S

It's a real shame a picture of the light levels as seen from the human eye wasn't taken - I reckon people might then appreciate the pics better.



The various xxxx-luminescence effects are not well understood, but happen most often with substances lacking a center of symmetry in their structure (not limited to crystalline substances). That is certainly the case with normal (quartz-based) sand which comes in left-handed and right-handed enantiomorphs..

Light flashes as precursors to earthquakes have often been reported, and probably have the same cause.
...

The only sure way to survive a canopy collision is not to have one.

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Yeah, I sometimes see similiar flashes emitting from the wife when I get home from the pub. . . :D

I reckon a further effect which can't be discounted is the simple mechanical effect - taking also into account the material which protects the leading edge of the blade.

But why are substances lacking a centre of symmetry more likely to cause such an effect?


'for it's Tommy this, an' Tommy that, an' "chuck 'im out, the brute!" But it's "saviour of 'is country" when the guns begin to shoot.'

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Yeah, I sometimes see similiar flashes emitting from the wife when I get home from the pub. . . :D



Don't need physics to explain THAT.

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I reckon a further effect which can't be discounted is the simple mechanical effect - taking also into account the material which protects the leading edge of the blade.

But why are substances lacking a centre of symmetry more likely to cause such an effect?



Easier to explain the opposite. IF there's a center of symmetry, then any deformation will move + and - charges equally, resulting in no charge separation and therefore no electric field to generate the flash.

Then in the absence of symmetry, the deformation will move the + and - charges unequally giving charge separation, this giving rise to an electric field.


Replace "deformation" with "fracture" in the above, and the same reasoning applies.
...

The only sure way to survive a canopy collision is not to have one.

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Easier to explain the opposite. IF there's a center of symmetry, then any deformation will move + and - charges equally, resulting in no charge separation and therefore no electric field to generate the flash.

Then in the absence of symmetry, the deformation will move the + and - charges unequally giving charge separation, this giving rise to an electric field.


Replace "deformation" with "fracture" in the above, and the same reasoning applies.



OK. But why is it necessary to do it in a garage? Must have missed something.
" . . . the lust for power can be just as completely satisfied by suggesting people into loving their servitude as by flogging them and kicking them into obedience." -- Aldous Huxley

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Easier to explain the opposite. IF there's a center of symmetry, then any deformation will move + and - charges equally, resulting in no charge separation and therefore no electric field to generate the flash.

Then in the absence of symmetry, the deformation will move the + and - charges unequally giving charge separation, this giving rise to an electric field.


Replace "deformation" with "fracture" in the above, and the same reasoning applies.



OK. But why is it necessary to do it in a garage? Must have missed something.



He already mentioned his wife. Where were you?
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The only sure way to survive a canopy collision is not to have one.

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A similiar effect can be seen if you go into your garage with a sugar cube and a hammer. Ensuring it's properly dark, and your eyes have adjusted (and you can remember where you've placed the sugar cube), smash it hard with the hammer and see what happens.



Alternatively it works well with a friend and Certs candy or Wint-O-Green Lifesavers too. B|

Used to do that as a Girl Scout Camp Counselor with the campers. :)
/Marg

Act as if everything you do matters, while laughing at yourself for thinking anything you do matters.
Tibetan Buddhist saying

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You think that's odd - google sonoluminescence.



"Bubbles hotter than the sun" :D

(One of my old research labs worked on sonoluminescence.)

/Marg

Act as if everything you do matters, while laughing at yourself for thinking anything you do matters.
Tibetan Buddhist saying

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You think that's odd - google sonoluminescence.



"Bubbles hotter than the sun" :D

(One of my old research labs worked on sonoluminescence.)

/Marg


A couple years ago a researcher made a fool of himself proclaiming that sonoluminesence was actually micro fission. Turns out his neutrino detector was sitting RIGHT NEXT to the neutrino generator used to create the micro bubbles. DOH.
~Bones Knit, blood clots, glory is forever, and chicks dig scars.~

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A couple years ago a researcher made a fool of himself proclaiming that sonoluminesence was actually micro fission. Turns out his neutrino detector was sitting RIGHT NEXT to the neutrino generator used to create the micro bubbles. DOH.



Yes, Rusi Taleyarkhan and sonoluminesce-induced cold fusion or "bubble fusion."

I've cited the case a few times (third, for 'few') in SC. It's, im-ever-ho, a great example of debates in science (they're not unprecedented; another fave is the great silylium super-acid debate), the adversarial nature of scientific pursuit, and correcting nature of peer review process, which extends beyond initial review of submitted manuscripts.

/Marg

Act as if everything you do matters, while laughing at yourself for thinking anything you do matters.
Tibetan Buddhist saying

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It's a real shame a picture of the light levels as seen from the human eye wasn't taken - I reckon people might then appreciate the pics better.



Long exposures like this are cool as hell - you can bring up an amazing amount of info from what looks like blackness. If he did a "normal" pic, all you'd see would be the a/c strobes and we'd be saying "Ok, is this it?"
Mike
I love you, Shannon and Jim.
POPS 9708 , SCR 14706

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No.

I meant it would have been good for one standard picture to be put alongside the others, so as to demonstrate the actual light levels for the viewer.:|

Hence people might appreciate the pictures better!:)
Anyway, I'm glad people enjoyed the article - I figured they might.


'for it's Tommy this, an' Tommy that, an' "chuck 'im out, the brute!" But it's "saviour of 'is country" when the guns begin to shoot.'

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