The Grass Is Yellower on the Other Side of the Cosmos

Counterintuitively colored plants are a standard plot device in interstellar science fiction, and two papers recently published in Astrobiology suggest that blood-hued grass and jaundiced trees may not be so far-fetched after all.

Scientists have long known that the chlorophyll in most plants on Earth absorbs blue and red light and less green light, appearing green.

But not all stars have the same distribution of light colours as our Sun. As a result, photosynthesis on these alien worlds will not necessarily look the same as on our home world.

This new research narrows the spectrum of colours that scientists would expect to see when photosynthesis is occurring on these so called extrasolar planets.

Each planet will have different dominant colours for photosynthesis, based on the planet’s atmosphere where the most light reaches the planet’s surface.

Better yet, the scientists hope to determine the unique wavelength signatures of light reflected by planets on which photosynthesis is taking place. As one researcher said with the sort of eternally goofy optimism that makes me proud to be human, "We want to know if we're alone in the universe. Photosynthesis produces global-scare signatures of life that can be seen from great distances, for example by future telescopes."

Ah, those future telescopes. Sign me up for some HD 209458b viewing time.

Alien plants 'more colourful than Earth's flora' [Telegraph]

Image: Kate Harrington