SF writer question...
Given that the color of plant life is dependent upon the type of light absorbed and reflected (the process itself dependent upon factors such as atmospheric chemistry, and the proximity and brightness of the star the planet happens to be orbiting, etc.), I'm wondering whether it would "theoretically" be possible to encounter an alien world possessed of darker purple or black vegetation (say on a planet orbiting a red dwarf) AND an atmosphere capable of sustaining human life? I stress "theoretically".
Thanks in advance.