Dark matter, why?

Hi oc It would really be something that a lot of dark matter can glow??
Being a scuba diver,and going on night dives you are amazed to see by
just clapping your hands and see all that light. An anchor rope will
glow when rubbed. If you walk along the shore on a moonless night and
see where the waves rub against the sand you will see a faint glow.
Can we be sure that blackholes don;t glow?? Neutron stars can be picked
up by the Hubble(I just learned that this month) If blackholes glow it
would be done just outside its event horizon. A place I visualize where
photons fall in or are lucky and can escape Bert

Dennis you are right it is a chemical molecular action created by
friction. Male fireflies use the light to attract the female for sex. If
I was a firefly I would be known as the "big flasher"
Bert