12 comments

  • colanderman 2 hours ago
    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/10.1029/2025GL11...

    [2] https://agupubs.onlinelibrary.wiley.com/action/downloadSuppl...

    • raincole 11 minutes ago
      That's some weird semantic nitpicking.

      Wikimedia has a category of "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.)

    • addaon 1 hour 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?
      • clickety_clack 59 minutes 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 47 minutes 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_t...

          • yetihehe 18 minutes 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.

          • ajkjk 46 minutes ago
            what's the job?
      • chrisfosterelli 58 minutes 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.

      • adammarples 1 hour ago
        Maybe they take issue with the word "glowing", which doesn't usually refer to invisible electromagnetic radiation
    • aaron695 1 hour ago
      [dead]
  • chankstein38 20 minutes ago
    I once was about 30-50ft from where lightning struck, standing on my porch looking towards my neighbors' house. I didn't see the actual strike happen but I did feel my hair stand on end and then see basically this coming off of the leaves reaching up towards the sky. Little purple tentacles all reaching upwards.

    But then I got to the point in the article where they seemed to explain this wasn't visible to the naked eye.... What did I see?

  • mlhpdx 2 hours ago
    Having lived in the PNW all my life, and worked closely with our friend Doug (the fir trees), this article brings up old mental images of otherwise healthy needles with browned (dead) tips in the crowns.

    Coincidence? Probably.

    Very cool phenomenon to catch visually.

    • t-3 1 hour ago
      Maybe not a coincidence! The previous research linked in the article mentions this in lab testing:

      https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022JD03...

        > Visually, the corona discharges generated on the leaves were either small purple-blue point discharges or elongated purple-blue discharges, and usually formed on the tips of the leaf closest to the source of the electric field (Figure 1). Sometimes the corona discharges were steady and constant, but other times they would dim and brighten in an unsteady pulse. When the corona was turned off, the tips of the leaf where the discharges occurred were often burned and browned, even for the weakest electric fields applied to the leaves.
    • colanderman 2 hours ago
      Despite the title, it was not in fact caught visually.
      • arrowleaf 1 hour ago
        Human eyes can be sensitive down to 380nm, the UV range goes up to 400nm. Birds and insects can see this. We can see this, using UV filters such as shown in the article. I get that it's fun to be a pedant sometimes, but come on.
  • antimora 33 minutes ago
    > “This just goes to show that there’s still discovery science being done,” said McFarland, lead author on the paper. “For more than half a century, scientists have theorized that corona exists, but this proves it.”

    "proves it" ?? What kind of science is that?

  • Lalabadie 2 hours ago
    Great time to read about St Elmo's Fire!

    https://en.wikipedia.org/wiki/St._Elmo's_fire

    • _joel 1 hour ago
      Sounds like a man in motion :)
  • calibas 1 hour ago
    I notice the article, the paper, and the "plain language" summary of the paper don't mention the common term for this phenomenon, St Elmo's fire.
  • ortusdux 1 hour ago
    It would be amazing if there was an electrical mechanism behind crown shyness.

    https://en.wikipedia.org/wiki/Crown_shyness

  • dreamlayers 1 hour ago
    What is new here? I thought corona discharges during storms had already been well known for a long time. https://en.wikipedia.org/wiki/St._Elmo%27s_fire
    • none2585 1 hour ago
      Article claims it had never been seen outside the lab before (for trees specifically I guess)
  • imzadi 1 hour ago
    I've seen these images before, or some very similar images. So this is based on old photos or it has indeed been done before.
  • wildylion 1 hour ago
    Storm troopers, but not the kind you'd expect.
  • brador 1 hour ago
    Will head hair on humans do this too?
  • GolfPopper 1 hour ago
    [dead]