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There is in fact no photograph of treetops glowing. There is a digital UV-wavelength video of the corona, and a visible-wavelength video of the trees. The pap

There is in fact no photograph of treetops glowing. There is a digital UV-wavelength video of the corona, and a visible-wavelength video of the trees. The paper [1] contains a sole picture with tiny circles indicating where the UV-video detected corona events, overlaid over a frame of the visible-wavelength video. The paper does also contain a video [2] which overlays a somewhat processed version of the UV video over the visible wavelength video, where UV photon events are indicated by decaying red dots. [1] https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL119591 https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL11... [2] https://agupubs.onlinelibrary.wiley.com/action/downloadSupplement?doi=10.1029%2F2025GL119591&file=2025GL119591-sup-0002-Movie+SI-S01.avi https://agupubs.onlinelibrary.wiley.com/action/downloadSuppl...

aaron695 5mo ago
[dead]
addaon 5mo ago
Sorry, in what way is this not a photograph? Are you saying that a video is not a sequence of photographs, that UV photons captured by a sensor don’t count because human retina sensitivity is low in that range, or some hopefully-less-semantic argument?
- adammarples 5mo ago
  Maybe they take issue with the word "glowing", which doesn't usually refer to invisible electromagnetic radiation
  - Brian_K_White 5mo ago
    I was going to say the same. It's true that the image isn't fiction or a purely fabricated "artists rendering" from data. But it's also true that "filmed" and "glowing" are unusual ways to refer to what happened. You don't usually say filmed when talking about recording uv or microwaves etc. You technically could, and probably back when film was actually how uv was recorded a few people working in the field probably did, but almost no one else does, or no one at all since decades, which means the author of the title is the one out of step, not the people reading it. They actually recorded something, and this title is misleading. Both things are true.
    - amluto 5mo ago
      When I worked in a lab that took videos with a UV camera, I still called them videos, and I would absolutely have said that I took a video of the subject (a methanol flame in this case). Essentially every color photograph you have ever seen is a composite of a red photographic, a green photograph, and a blue photograph.
- clickety_clack 5mo ago
  The headline suggests that people have seen treetops glowing and it just hasn’t been captured on video before. The actual pictures and video is of something that nobody could have seen with their eyes.
  - WarmWash 5mo ago
    You can absolutely see corona discharge like that with your eyes. If you come to my day job, and we shut off all the lights in the test room, after your eyes adjust in the dark for a minute, you'll see the soft purple glow coming from the edge our 160kV test rig. Definitely emits UV, but there is enough visible to see it for sure. It comes from the electrons exciting nitrogen in the air.[1] 1. https://commons.wikimedia.org/wiki/File:Nitrogen_discharge_tube.jpg https://commons.wikimedia.org/wiki/File:Nitrogen_discharge_t...
    - ajkjk 5mo ago
      what's the job?
    - yetihehe 5mo ago
      > (1:If you come to my day job), and (2: we shut off all the lights) (3:in the test room), (4:after your eyes adjust in the dark for a minute), you'll see the soft purple glow coming (5:from the edge our 160kV test rig). So, 5 different things that make it glow "not coming from treetops". Parent poster wanted to see glowing treetops in a forest, where we might not be adjusted to dark for a minute. You can also see such corona discharge with benchtop tesla coils even in lighted room, but those are not trees in forest glowing from a storm.
      - MisterTea 5mo ago
        Even a smallish Tesla coil easily produces voltages north of 160kV. I built one using 4" PVC for the secondary with a wound length of maybe ~2 feet of secondary? From memory of the calculations I did at the time I think it was around 350 kV peak? Might have been higher. Threw 24 inch sparks quite easily.
- chrisfosterelli 5mo ago
  I don't really blame the researchers here but this is yet another article that is happy to have a clickbait headline which any reasonable reader is going to assume will include a picture of "treetops glowing". At least personally I scanned the article for it and only found the picture at the top, which I was then frustrated to learn that's just a lab photo, and I came here wondering where the actual image is of it in the field so I found OPs comment helpful to indicate that the suggestion there would be a beautiful picture of glowing canopy somewhere is basically a result of editorializing.
- colanderman 5mo ago
  Which photograph? The one in the article is not from the paper. The paper contains no photographs of corona.
raincole 5mo ago
That's some weird semantic nitpicking. Wikimedia has a category of "photographs of the Sun": https://commons.wikimedia.org/wiki/Category:Photographs_of_the_Sun https://commons.wikimedia.org/wiki/Category:Photographs_of_t... Do you think they are not photographs of the Sun because these are not what I see if I look at the sun with my eyes? (In which case I'll see pure white then perma black, I assume.)
- latexr 5mo ago
  > then perma black, I assume. Probably not. https://www.bbc.com/news/blogs-ouch-31487662 https://www.bbc.com/news/blogs-ouch-31487662
  - dugidugout 5mo ago
    This was a very depressing read.
  - YeahThisIsMe 5mo ago
    What he explains sounds exactly like what you (or at least I) see when you close your eyes and then put pressure on them.
    - doubletwoyou 5mo ago
      The way I had it explained was trying to look out one eye while the other’s closed
  - steve1977 5mo ago
    While reading I thought this is basically visual tinnitus and then the author used exactly that term. As someone with tinnitus, I can definitely understand the longing for "absolute darkness".
- t-3 5mo ago
  They're the same as looking at the sun with your eyes. You won't go blind looking directly for a short time. It's just best not to stare for a long time.
Bjartr 5mo ago
While we're being unreasonably pedantic, it also wasn't caught on film because it was a digital camera.
dang 5mo ago
I've taken the "captured on film" out of the title above and used representative language from the article. If someone can suggest a better (more accurate and neutral) title, we can change it again. (But the subject is interesting whether on film or not, let alone "for the first time".)
_Microft 5mo ago
Half of the comments are in this subthread which derailed the discussion on this submission before it even started. Here the damage is done but maybe, please, refrain from doing so elsewhere.

aaron695 5mo ago

[dead]

addaon 5mo ago

Sorry, in what way is this not a photograph? Are you saying that a video is not a sequence of photographs, that UV photons captured by a sensor don’t count because human retina sensitivity is low in that range, or some hopefully-less-semantic argument?

adammarples 5mo ago
Maybe they take issue with the word "glowing", which doesn't usually refer to invisible electromagnetic radiation
- Brian_K_White 5mo ago
  I was going to say the same. It's true that the image isn't fiction or a purely fabricated "artists rendering" from data. But it's also true that "filmed" and "glowing" are unusual ways to refer to what happened. You don't usually say filmed when talking about recording uv or microwaves etc. You technically could, and probably back when film was actually how uv was recorded a few people working in the field probably did, but almost no one else does, or no one at all since decades, which means the author of the title is the one out of step, not the people reading it. They actually recorded something, and this title is misleading. Both things are true.
  - amluto 5mo ago
    When I worked in a lab that took videos with a UV camera, I still called them videos, and I would absolutely have said that I took a video of the subject (a methanol flame in this case). Essentially every color photograph you have ever seen is a composite of a red photographic, a green photograph, and a blue photograph.
clickety_clack 5mo ago
The headline suggests that people have seen treetops glowing and it just hasn’t been captured on video before. The actual pictures and video is of something that nobody could have seen with their eyes.
- WarmWash 5mo ago
  You can absolutely see corona discharge like that with your eyes. If you come to my day job, and we shut off all the lights in the test room, after your eyes adjust in the dark for a minute, you'll see the soft purple glow coming from the edge our 160kV test rig. Definitely emits UV, but there is enough visible to see it for sure. It comes from the electrons exciting nitrogen in the air.[1] 1. https://commons.wikimedia.org/wiki/File:Nitrogen_discharge_tube.jpg https://commons.wikimedia.org/wiki/File:Nitrogen_discharge_t...
  - ajkjk 5mo ago
    what's the job?
  - yetihehe 5mo ago
    > (1:If you come to my day job), and (2: we shut off all the lights) (3:in the test room), (4:after your eyes adjust in the dark for a minute), you'll see the soft purple glow coming (5:from the edge our 160kV test rig). So, 5 different things that make it glow "not coming from treetops". Parent poster wanted to see glowing treetops in a forest, where we might not be adjusted to dark for a minute. You can also see such corona discharge with benchtop tesla coils even in lighted room, but those are not trees in forest glowing from a storm.
    - MisterTea 5mo ago
      Even a smallish Tesla coil easily produces voltages north of 160kV. I built one using 4" PVC for the secondary with a wound length of maybe ~2 feet of secondary? From memory of the calculations I did at the time I think it was around 350 kV peak? Might have been higher. Threw 24 inch sparks quite easily.
chrisfosterelli 5mo ago
I don't really blame the researchers here but this is yet another article that is happy to have a clickbait headline which any reasonable reader is going to assume will include a picture of "treetops glowing". At least personally I scanned the article for it and only found the picture at the top, which I was then frustrated to learn that's just a lab photo, and I came here wondering where the actual image is of it in the field so I found OPs comment helpful to indicate that the suggestion there would be a beautiful picture of glowing canopy somewhere is basically a result of editorializing.
colanderman 5mo ago
Which photograph? The one in the article is not from the paper. The paper contains no photographs of corona.

raincole 5mo ago

That's some weird semantic nitpicking. Wikimedia has a category of "photographs of the Sun": https://commons.wikimedia.org/wiki/Category:Photographs_of_the_Sun https://commons.wikimedia.org/wiki/Category:Photographs_of_t... Do you think they are not photographs of the Sun because these are not what I see if I look at the sun with my eyes? (In which case I'll see pure white then perma black, I assume.)

latexr 5mo ago
> then perma black, I assume. Probably not. https://www.bbc.com/news/blogs-ouch-31487662 https://www.bbc.com/news/blogs-ouch-31487662
- dugidugout 5mo ago
  This was a very depressing read.
- YeahThisIsMe 5mo ago
  What he explains sounds exactly like what you (or at least I) see when you close your eyes and then put pressure on them.
  - doubletwoyou 5mo ago
    The way I had it explained was trying to look out one eye while the other’s closed
- steve1977 5mo ago
  While reading I thought this is basically visual tinnitus and then the author used exactly that term. As someone with tinnitus, I can definitely understand the longing for "absolute darkness".
t-3 5mo ago
They're the same as looking at the sun with your eyes. You won't go blind looking directly for a short time. It's just best not to stare for a long time.

Bjartr 5mo ago

While we're being unreasonably pedantic, it also wasn't caught on film because it was a digital camera.

dang 5mo ago

I've taken the "captured on film" out of the title above and used representative language from the article. If someone can suggest a better (more accurate and neutral) title, we can change it again. (But the subject is interesting whether on film or not, let alone "for the first time".)

_Microft 5mo ago

Half of the comments are in this subthread which derailed the discussion on this submission before it even started. Here the damage is done but maybe, please, refrain from doing so elsewhere.