When reading something like “Cat’s urine glow under a black light” I immediately though about useless information.
However it’s not that useless after all because it allows the owner to investigate if his pet is misbehaving. I should start a series called “useful information”…
Anyway, cat’s urine glows very brightly under ultraviolet light because it has fair amounts of phosphorous.
Now you know. Get a black light and start your investigations.