So I just saw the YouTube video someone posted that showed nuclear reactors starting up, and the first thing I noticed was that they all glowed a very bright, pretty blue. I’m probably an idiot, but I was honestly expecting green, because of many years of dramatized depictions in popular media.

These are probably dumb questions, but:

  1. Why is it blue? As in, what’s actually glowing in there, and why do we see it that way?

and

  1. Why do all the movies and comic books and video games go with green instead? Where did that come from?
    • panoptic
      40•1 year ago

      I’m almost certain this is it.

      Most people’s experience in the early days with “glowing radioactive stuff” would have been radium paint, which glows green.

      Normal people wouldn’t have seen Cherenkov radiation (blue glow)

      Edit: just to make it clear, stuff painted with radium paint was not uncommon decades ago
      Source: I’m gettin kinda old

      • Bucket_of_Truth
        16•1 year ago

        Tritium glows bright green and is used in a lot of consumer products, specifically gun sights and watches. Uranium glass also glows bright green.

        Maybe people think radioactive things glow green because… they often do glow green.