We may have no proof that aliens exist, but US astrophysicist Adam Frank is pretty convinced. -- Best Holiday Reading - New Scientist Pleasingly, the findings here are more hopeful and proactive than has been the case elsewhere, encouraging us to take charge and create a better future. As far as messages go, it's not a bad one. -- How It Works In this provocative new book, Adam Frank makes the case that one good way to think about life on Earth is to think about the prospect of life on other planets-and what it might have to teach us about how to be good Earthlings. -- Sean Carroll