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As a father to a small child, I have often observed this phenomenon but have until i posted this question not found the vocabulary to Google for it.

Can you explain what I am seeing?

In a darkened room I see a faint light appearing when:

  1. pouring a quantity of urine from a potty into a toilet (I will spare you the image) Update possibly urine chemiluminescence - however I think that is when it gives off light on its own - without being poured

  2. pulling something apart (UPDATE it is called Triboluminescence) that was taped together on purpose such as
    a) the fasteners on a modern diaper
    b) opening a band-aid "envelope" Band-aid (please note that I had not used the word "band-aid" until I was looking for an image to describe what I was pulling)

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Second question (v5) is a duplicate of – Qmechanic Apr 19 '12 at 15:10

The light from urine is called "spontaneous urinary luminescence", but I'm not sure anyone really knows what causes it. It's thought to be due to organic molecules getting into the urine from the body, and it seems to be enhanced by some medical conditions like muscular dystrophy.

Thanks to anna v for: A link for when it is enhanced.

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I saw the smoker thing - but ignored it since I expected it to be glowing on its own. In my case it lights up when it hits the cold water/porcelain of the toilet. I certainly hope it is not due to any disease - I found urine chemiluminescence – mplungjan Apr 19 '12 at 14:20
Thanks for the link Anna. @mplungjan: it hadn't occurred to me to Google for "urine chemiluminescence", though it doesn't seem to find anything very definitive. I still get the impression no-one really knows what's going on. I must admit I have never observed this phenomenon; maybe I shall wee in the dark tomorrow morning to see what happens :-) – John Rennie Apr 19 '12 at 14:32
It is not clear to me if the urine (chemo)luminescence is in still urine or when "exited" - my phenomenon is when poured onto something else only ;) – mplungjan Apr 19 '12 at 14:37
@JohnRennie Don't do that, unless you clean your toilet yourself. Otherwise you'll be hearing stuff from your wife... :) – Pygmalion Apr 19 '12 at 17:04

...but have not found the vocabulary to Google for it.

I have never heard of the phenomenon before. So I just typed "light band aid" into google and this page on Triboluminescence is the result. The example section on the page mentions your example and others. You seriously need to work on your google-fu.

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Except I did not use the word band-aid until I wrote the question. So it did not occur to me to use that again in a google search. We do not use band-aids in the rest of the world since it is a brand name. Not sure why you were voted down... Interestingly enough, had I used "Breathe Right" and light, I would have found it – mplungjan Apr 19 '12 at 13:21
Great - that was one of them. And the other? – mplungjan Apr 19 '12 at 13:26
@mplungjan: I assume I got the downvote because of the douchy answer. Good people from the academia sector often develope a there are no stupid questions attitude, which confronts the sarcastic let me google that for you internet philosophy. StackExchange answers should also contain explainations and not just links. However, in that case I think it's not worth anyones time to write an elaboration when, after reading the wikipage and references therein, you might actually have some new physical questions. – NikolajK Apr 19 '12 at 13:30
Feel free to remove your sarky parts and just answer - I +1 your answer awaiting that. As I said, I did not actively use the word band-aid which was the reason I did not find anything. I now have the vocabulary of luminescence and band-aid, but I cannot find anything on the Urine version – mplungjan Apr 19 '12 at 13:33

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