Informative and fascinating, this book delves into the topic of extraterrestrial life in a thought-provoking yet scientifically responsible way. Are we alone in the universe, or is life a universal phenomenon? For fifty years, astronomers in SETI (Search for Extraterrestrial Intelligence) have scanned the universe for intelligent signals, but with no success. In this intriguing book, Edward Ashpole explains the probable reasons for this and discusses other avenues of investigation more in line with the nature of science and technology. The author examines the problems inherent in scanning the universe for radio or optical signals from an alien intelligence. These include the difficulty of trying to communicate with another species possessing a completely unknown form of technology and the vast distances that alien communications would have to travel to reach us. This leads the author to other ways of finding evidence for extraterrestrial life, given that advanced civilizations would probably use artificial intelligence for interstellar travel. Our scientists now know how to detect the presence of life on a planet by observing its spectral lines, so more advanced alien researchers
