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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."
Anyone else read this as "Worlds With Two Suns May Sport Black Pants?"
https://www.eff.org/https-everywhere
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).
The sky is blue because if it were white, we couldn't see the clouds.
When our name is on the back of your car, we're behind you all the way!
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).
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.
So a lot like Canada then?
XML is a known as a key material required to create SMD: Software of Mass Destruction
If you're talking about a system with 2 very similar stars in terms of distance, length of day, intensity, etc.
But what if one star is dominant? At what point is it not worth harvesting light from the secondary star?
Rather than black plants that absorb a fuller range of frequencies, you might get 2 parallel evolutionary paths. Green trees would grow tall from the light of the large yellow star, while the underbrush would be full of red leafy ferns which absorb light from the smaller star.
Evolution causes mother nature to be very efficient in her selection of characteristics. It might just be that green is useful to plants because it is the right wavelength for efficient photosynthesis with the sun's light. It might be green because it's much easier for plants to make green chloroplasts than other colors or because green imparts enough energy without overheating the leaf structure or its easier for plants to repair green proteins than other colors. If you read up on it a bit, you find out that green does not really maximize energy production, but it's apparently optimal for most plants. However, there's plenty of earth plants that aren't green! Surprisingly there's few black plants. We think too often about optimizing a single parameter. Usually that parameter is short term cash flow. The natural world is a more-or-less true form of capitalism and it's brutal but it shows us that short-term gain isn't the only thing worth maximizing and in nature there's no way to externalize costs for the long-term. Those that do, don't survive.
Plants don't "maximize energy absorption for photosynthesis" on Earth so why leap to the assumption that they would elsewhere. In fact Green is just about the worst color (lets ignore white) they could use on Earth. And retinal exists and is much better than chlorophyll in terms of using the "right" part of the spectrum to get more energy from sunlight (though I think it's then less efficient at harnassing it).
And of course absorbing too much energy can be a bad thing, heat is an unavoidable product (the atronomers should know that at least, thermodnamics is pretty important to their field...).
Evolution does not produce perfection, it creeps toward local maximas in the fitness space - OK now the biologists can call me stupid :)