These materials are transparent to some light. They absorb a lot of infrared and ultraviolet. The human vision system can see the light that isn't absorbed and as a result is abundant in our environment.
These materials are transparent to some light. They absorb a lot of infrared and ultraviolet. The human vision system can see the light that isn't absorbed and as a result is abundant in our environment.
The good news is that most stars have a spectrum very roughly similar to ours, so we can expect that aliens can probably see these wavelengths.