Plants May Not Be Green Under Different Suns

Germany’s Black Forest is in fact pretty green, but scientists at NASA predict that there may be real black forests on Earth-like planets orbiting stars emitting different wavelengths than our Sun. Photosynthesis on our planet absorbs essentially red and blue wavelengths of the visible spectrum, causing the plants to appear green to our eyes. On other worlds where life may have appeared, this process is expected to absorb different radiations, depending on the type of star the planet is orbiting. Thus, the local vegetation could appear orange, red, or completely black to human eyes.

As photosynthesis is a dominant process for life, it could be detected in distant planets as evidence that life has appeared and evolved there as well. However, the planet-finding process needs to be refined, as we are only currently able to locate Jupiter-like gaseous giants that are unlikely to harbor identifiable life forms.

The scientists studied light absorbed and reflected by organisms on Earth, and determined that if astronomers were to look at the light given off by planets circling distant stars, they might predict that some planets have mostly non-green plants.

Source: NASA