His native world Tatooine is a desert planet. But two suns in the sky would be a big deal for vegetation on a tropical planet, reports Jack O'Malley-James of the University of St. Andrews in Scotland. He recently presented a study at a Royal Astronomical Society meeting in Llandudno, Wales.
Given the power of biological evolution, plant life would adapt to use energy from both suns. Or perhaps different forms of plants may evolve to use light from one specific sun, he reported.
Things could get complicated in multiple systems that have a yellow sun-like star with a red dwarf companion. Over 25 percent of sun-like stars and 50 percent of red dwarfs are found in multi-star systems. The plants would have access to a broader range of radiation than on Earth. Stellar radiation would stretch far into infrared wavelengths.
"Our simulations suggest that planets in multi-star systems may host exotic forms of the more familiar plants we see on Earth," says O'Malley-James.
Plants
In 2008, astrobiologist Nancy Kiang of Columbia University predicted that alien plants living under a red sun could evolve other photosynthetic pigments that are colored purple, or even black (O'Malley-James speculates black or gray coloring).
Unlike Earth vegetation that reflects some green light, alien vegetation might absorb across the entire visible wavelength range in order to use as much of the available light as possible. They may also be able to use infrared or ultraviolet radiation to drive photosynthesis.
Due to their interior structure, red dwarf stars can be more petulant than a solar-type star. A Hubble Space Telescope survey of 215,000 red dwarfs uncovered 100 powerful stellar flares over a seven-day period. Despite their puny mass, red dwarfs can pack a punch.
Read more at Discovery News
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