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 roughly similar to ours (not too much infrared or ultraviolet) so we can expect that aliens can probably see these wavelengths.
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 roughly similar to ours (not too much infrared or ultraviolet) so we can expect that aliens can probably see these wavelengths.