We've long been led to believe that astronomers spend every night searching the sky for extraterrestials, but the truth is we have barely started looking. Not until now have we even known where to look or how. In The Little Book of Aliens, Frank, a leading researcher in the field, takes us on a journey to all that we know about the possibility of life outside planet Earth and shows us the cutting-edge science that has brought us to this unique moment in human history: the one where we go find out for ourselves.