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This somehow reminds me of the fact that you can produce (surprisingly high-quality) x-rays by unrolling scotch tape in a vacuum chamber[0][1]. I wonder if it t

This somehow reminds me of the fact that you can produce (surprisingly high-quality) x-rays by unrolling scotch tape in a vacuum chamber[0][1]. I wonder if it turns out to be related in any way. Thunderstorms aren't a vacuum of course, but I dunno, maybe all that frozen hail being thrown around can bumping into each other still involves a similar underlying mechanism somewhere. [0] https://www.nature.com/articles/nature07378 https://www.nature.com/articles/nature07378 [1] https://www.youtube.com/watch?v=-o66AYhEIsU& https://www.youtube.com/watch?v=-o66AYhEIsU&

genocidicbunny 2y ago
You don't even need a vacuum to get a decent amount of xrays. Two drills going through a roll of scotch, reel to reel, will generate enough x-rays to take a rudimentary xray image of a hand.
westurner 2y ago
What about guitar pedal velcro tape? [0] "Correlation between nanosecond X-ray flashes and stick–slip friction in peeling tape" (2008) https://www.nature.com/articles/nature07378 https://www.nature.com/articles/nature07378 > Triboluminescence is a phenomenon in which light is generated when a material is mechanically pulled apart, ripped, scratched, crushed, or rubbed (see tribology). [...] Triboluminescence is often a synonym for fractoluminescence (a term mainly used when referring only to light emitted from fractured crystals). Triboluminescence differs from piezoluminescence in that a piezoluminescent material emits light when deformed, as opposed to broken. These are examples of mechanoluminescence, which is luminescence resulting from any mechanical action on a solid. [...] See also: > - Earthquake light: https://en.wikipedia.org/wiki/Earthquake_light https://en.wikipedia.org/wiki/Earthquake_light - re: gold from earthquake-induced piezoelectricity in quartz: https://news.ycombinator.com/item?id=41442489 https://news.ycombinator.com/item?id=41442489 - re: sustainable alternatives to quartz countertops: https://news.ycombinator.com/item?id=36857929 https://news.ycombinator.com/item?id=36857929 : > [...] make recycled paper outdoor waterproof vert ramps, countertops, siding, and flooring; but not yet roofing FWIU? > - Sonoluminesence: https://en.wikipedia.org/wiki/Sonoluminescence https://en.wikipedia.org/wiki/Sonoluminescence
abc_lisper 2y ago
It was suprising to me when I heard it. How could we not know it would happen before hand? Doubt explanation of it needs new laws of physics, item is common place and yet we were all caught off-guard. Wonder who different other planets even in our own solar system are, even if we know all the laws of physics and chemistry that guide those reactions; never mind planets in other solar systems
Andys 2y ago
When objects collide or are separated, aren't we really just witnessing tiny chemical reactions, all involving the absorption and/or release of energy?
- LorenPechtel 2y ago
  No. "Gamma rays" in modern scientific usage has a specific meaning: radiation coming from the nucleus or from annihilation reactions (electron + positron is considered a gamma source despite not involving a nucleus), not from the electrons. The energy bands actually overlap, you can't always tell whether a given photon is without understanding it's source. (The lowest energy gamma rays actually fall in the UV part of the spectrum.) And what they're saying is the energy of the lightning is acting as a particle accelerator. aka atom smasher. And there's a surprising level of atom smashing going on in the big thunderclouds.
- vanderZwan 2y ago
  I think that's a reasonable question, but no, I wouldn't say that that is the case. A chemical reactions is by definition the kind that involves changing the chemical composition of the molecules involved (yes, that's a bit handwavy, I'm not a chemist). The process that causes tape to produce to x-rays when peeled in a vacuum in this example does involve a change of energy states, but not in a way that we'd consider a change in chemical composition.
  - Andys 2y ago
    What is holding the tape to itself, what is making it sticky, if not chemistry?
    - mgsouth 2y ago
      For pressure-sensitive-adhesive tape (cellophane tape) it's mainly fuzzy static cling--wetting and van Der Waal's forces [1]. Wetting is when two substances (even solids) intermingle at their interface. van Der Waal's force is when a negatively-charged area of one molecule lines up the a postively-charged area of another. [1] https://science.howstuffworks.com/innovation/everyday-innovations/adhesive-tape.htm https://science.howstuffworks.com/innovation/everyday-innova...

genocidicbunny 2y ago

You don't even need a vacuum to get a decent amount of xrays. Two drills going through a roll of scotch, reel to reel, will generate enough x-rays to take a rudimentary xray image of a hand.

westurner 2y ago

What about guitar pedal velcro tape? [0] "Correlation between nanosecond X-ray flashes and stick–slip friction in peeling tape" (2008) https://www.nature.com/articles/nature07378 https://www.nature.com/articles/nature07378 > Triboluminescence is a phenomenon in which light is generated when a material is mechanically pulled apart, ripped, scratched, crushed, or rubbed (see tribology). [...] Triboluminescence is often a synonym for fractoluminescence (a term mainly used when referring only to light emitted from fractured crystals). Triboluminescence differs from piezoluminescence in that a piezoluminescent material emits light when deformed, as opposed to broken. These are examples of mechanoluminescence, which is luminescence resulting from any mechanical action on a solid. [...] See also: > - Earthquake light: https://en.wikipedia.org/wiki/Earthquake_light https://en.wikipedia.org/wiki/Earthquake_light - re: gold from earthquake-induced piezoelectricity in quartz: https://news.ycombinator.com/item?id=41442489 https://news.ycombinator.com/item?id=41442489 - re: sustainable alternatives to quartz countertops: https://news.ycombinator.com/item?id=36857929 https://news.ycombinator.com/item?id=36857929 : > [...] make recycled paper outdoor waterproof vert ramps, countertops, siding, and flooring; but not yet roofing FWIU? > - Sonoluminesence: https://en.wikipedia.org/wiki/Sonoluminescence https://en.wikipedia.org/wiki/Sonoluminescence

abc_lisper 2y ago

It was suprising to me when I heard it. How could we not know it would happen before hand? Doubt explanation of it needs new laws of physics, item is common place and yet we were all caught off-guard. Wonder who different other planets even in our own solar system are, even if we know all the laws of physics and chemistry that guide those reactions; never mind planets in other solar systems

Andys 2y ago

When objects collide or are separated, aren't we really just witnessing tiny chemical reactions, all involving the absorption and/or release of energy?

LorenPechtel 2y ago
No. "Gamma rays" in modern scientific usage has a specific meaning: radiation coming from the nucleus or from annihilation reactions (electron + positron is considered a gamma source despite not involving a nucleus), not from the electrons. The energy bands actually overlap, you can't always tell whether a given photon is without understanding it's source. (The lowest energy gamma rays actually fall in the UV part of the spectrum.) And what they're saying is the energy of the lightning is acting as a particle accelerator. aka atom smasher. And there's a surprising level of atom smashing going on in the big thunderclouds.
vanderZwan 2y ago
I think that's a reasonable question, but no, I wouldn't say that that is the case. A chemical reactions is by definition the kind that involves changing the chemical composition of the molecules involved (yes, that's a bit handwavy, I'm not a chemist). The process that causes tape to produce to x-rays when peeled in a vacuum in this example does involve a change of energy states, but not in a way that we'd consider a change in chemical composition.
- Andys 2y ago
  What is holding the tape to itself, what is making it sticky, if not chemistry?
  - mgsouth 2y ago
    For pressure-sensitive-adhesive tape (cellophane tape) it's mainly fuzzy static cling--wetting and van Der Waal's forces [1]. Wetting is when two substances (even solids) intermingle at their interface. van Der Waal's force is when a negatively-charged area of one molecule lines up the a postively-charged area of another. [1] https://science.howstuffworks.com/innovation/everyday-innovations/adhesive-tape.htm https://science.howstuffworks.com/innovation/everyday-innova...