Finding Plants on Exoplanets

Thanks to the movies, we think of alien life as intelligent, civilized creatures, mainly because they traveled here to visit us. But even though we haven't mastered travel to other planets yet, we can see exoplanets better than ever. And there are plenty of astronomers who have their eyes out for signs of life. But how can you detect life on planets so far away? It's easier when you think of that life as plants.

In 1990, scientists conducted an experiment dreamed up by Carl Sagan. When the the Galileo spacecraft flew by earth, it took measurements and observations to determine if there was life on this planet. The point was to determine how life could be detected on newly discovered planets. And the markers were there, indicating that earth held plant life. There was enough oxygen present that it had to be generated from something on the planet. And there was the way the surface reflected infrared light, but absorbed red light, just the way plants do. This gives us some ideas of what to look for in exoplanets. Read about the signs and signals that may indicate vegetation elsewhere in our galaxy at BBC Future. -via Damn Interesting