This book looks into the size of the universe around us, assesses the probability of aliens' existence, imagines their likely physical appearance, and finally investigates solutions for exploring the universe and colonializing other planets. Several interesting questions are considered such as: why maternity clinics would be needed on future interplanetary vessels? Why aliens, if they exist, would be very different from how they are depicted in science fiction movies? Why these aliens may have originated from our Earth? Etc. This book should be seen as a scientific introduction to the problem of space exploration. It has been written in a witty easy style and offers an exciting reading for young and old alike.