ZZBunker wrote:

It's makes perfect sense, since CBMR concerns dissociated hygrogen and
helium clouds, not Uranium clouds.

And it only concerns Kelvin because QM people
are more Background clueless than they
are cosmic clueless.

A quick glance into the night sky demonstrates that on average the
universe is not bright enough to stimulate the color receptors in the
human eye. So for humans, the universe on average cannot be directly
seen as having any color. Amplified images can be made, but then we're
just looking at glowing phosphors or illuminated pigments. Perhaps it
does have an average color for some other beings with more sensitive sight.
--
Lou Boyd