Worlds With Two Suns May Sport Black Plants

sciencehabit writes "If Tatooine were real, it would probably be filled with black plants and trees. A new study finds that, to maximize energy absorption for photosynthesis, the flora on worlds that orbit two suns may have evolved to use one or more types of light-absorbing pigments that absorb across a broad range of wavelengths, which would tend to make the plant appear black or gray. Although the idea that planets that could host such life may sound far-fetched, such orbs may not be so rare: The team's computer simulations indicate that Earth-like planets can exist in several types of stable orbits in multistar systems. More than one-fourth of the sunlike stars in our galaxy and about half of the long-lived but dim, cool stars called red dwarfs are found in solar systems containing two or more stars, the researchers note."

Planets around two suns probably would be lifeless

[scharkalvin]

The problem is that most of the stable orbits for a planet in a binary system result in very hot temperatures for part of it's orbit and freezing for the rest of the orbit.
1: planet orbits one of the two suns and is between two suns for part of orbit.
2: planet orbits both suns in a highly elliptical orbit taking it in and out of the 'goldilocks' zone where liquid water can exisit.
3: planet orbits both suns in a figure 8 orbit with similar results to #2

If BOTH suns are small and close together the planet could orbit both at a 'just right' distance to allow liquid water, but might be too close to the suns and be rotation locked with days and nights 1/2 a year long (like our moon).

teamâ½ Â s

[Eunuchswear]

Wah?

Re:Spam

[adonoman]

But absorption has to be balanced with water-retention and a host of other factors. If absorbing more of the spectrum is good, then why aren't all plants on earth black? The fact that we see them as green implies that they are reflecting back at least some of the spectrum (it turns out chlorophyll is surprisingly poor at absorbing green light).