Alien Skies: A Travelogue of the Universe gives readers the opportunity to travel through the universe, visiting a series of celestial destinations carefully chosen to span the extraordinary limits of space and time that bound our amazing cosmos. The destinations in Alien Skies reveal the unusual skies seen from throughout the solar system, nearby stars, nebulae, and star clusters, and during a series of voyages exploring the structure and content of our home galaxy. The itinerary includes nearby 'normal' galaxies, exotic active galaxies, as well as galaxy groups, clusters and cosmic voids. The final destinations of the journey traverse space and time to view the evolution of galaxies and cosmic structure, and of the universe as a whole. Alien Skies provides a broad, factual overview of modern astronomy, while instilling interest and enthusiasm of how science reveals the wonders of our universe. This book can serve as the text for introductory courses aimed at non-science majors or as background for courses geared to astronomy and astrophysics majors. It is also suitable for advanced courses at the high school level.