It isn't. Cat urine is not fluorescent, and it does not glow in the dark. I'm not sure where this myth comes from. Cat urine is yellow, like human urine. To the naked eye, it is indistinguishable from human urine, except for the smell. Cat urine is ammonia-based (unlike human urine) so it smells of ammonia.

You cannot get any diseases from human urine. In fact, human urine is sterile and so it cannot carry any diseases.

Normally human urine has a pH of about 6 which makes it an acid. However if something is not right the pH of urine can be higher or lower which could make the urine basic but this is not normal.

Yes, human urine is a good compost activator, particularly when diluted with 3 parts water to 1 part urine.

no