How would you react to such news? Would you join an impromptu street party, or start digging out a bunker in your backyard? Would the revelation usher in world peace – or worldwide panic? What would the message say and how would we respond? And what might our far away neighbors be like?

These are some of the questions deliberated by Seth Shostak, head astronomer at SETI (Search for Extraterrestrial Intelligence) in his new book Confessions of an Alien Hunter: A Scientist’s Search for Extraterrestrial Intelligence. In layman’s terms, Shostak describes the work that the SETI Institute has been doing for twenty-five years, the science behind the equipment and procedures currently being used to search for radio signals from other stars, and the emerging technologies that he predicts will find such a signal within the next few decades. Shostak also discusses the questions the institute’s scientists most frequently receive from Earthlings both supportive and critical of SETI’s mission: Where in the universe is other intelligent life likely to be found? Are aliens already here? Will we soon be zipping around space like the crew of the Enterprise? What might the aliens look like? Some of Shostak’s conclusions are sure to surprise you. (Think the aliens will have tentacles and six legs? Think again.)

Whether you’re a skeptic or a believer, Confessions of an Alien Hunter is a fascinating, good-humored look at one of the most popular and controversial topics of the modern era.