Wednesday, January 23, 2013
Life Light: the Next Frontier in Astronomy
To learn more about these planets, astronomers would like to separate out their reflected light from the rest of the light coming from the star. A hard trick, that, considering how dim a planet is compared to a star. But if they could do this, astronomers think, they might be able to analyze the light's spectrum and find the signatures of organic compounds that might indicate the presence of life. There are a lot of ifs here, but in principle it would work, and after all telescope technology is making great strides. The basic idea is to create an artificial eclipse by screening out the star's light. There are several competing methods of doing this, some of which are described in the graphic I lifted from Nature.
It is exciting to think that within another decade or two we might be able to read the chemical signatures of far-away planets and learn about their atmospheres and even, maybe, whether they might host carbon-based life. After all, 20 years ago extra-solar planets were only a theory.