Space experiments have opened practically all electromagnetic windows on the Universe. A discussion of the most important results obtained with multi-frequency photonic astrophysics experiments will provide new input to advance our knowledge of physics, very often in its more extreme conditions. A multitude of high quality data across the whole electromagnetic spectrum came at the scientific community's disposal a few years after the beginning of the Space Era. With these data we are attempting to explain the physics governing the Universe and its origin, which continues to be a matter of the greatest curiosity for humanity. In this book we describe the latest steps of the investigations born with the advent of space experiments. We highlight the most important results, identify unsolved problems, and comment on perspectives we can reasonably expect. This book aims to provide a useful tool for the reader who is not specialized in space astrophysics and for students. Therefore, the book is written in the form of a review with a still reasonable length, taking into account the complexity of the arguments discussed. We do not claim to present a complete picture of the physics governing the Universe, but have rather selected particular topics for a more thorough discussion. A cross section of essays on historical, modern, and philosophical topics is offered and combined with personal views into tricks of the space astrophysics trade.