author : Caleb ScharfCaleb Scharf is the director of the Columbia Astrobiology Center. He writes the Life, Unbounded blog for Scientific American; has written for New Scientist, Science, and Nature, among other publications; and has served as a consultant for the Discovery Channel, the Science Channel, TheNew York Times, and more. Scharf has served as a keynote speaker for the American Museum of Natural History and the Rubin Museum of Art, and is the author of Extrasolar Planets and Astrobiology, winner of the 2011 Chambliss Astronomical Writing Award from the American Astronomical Society. He lives in New York City with his wife and two daughters.