THIS ENDS the very extensive and remarkably good review of space weather, which is a backdrop for the effects of Earth’s weather. We rarely have, in a single review, such a comprehensive and detailed summary of conditions in space, written in accessible language, describing a universe that is far from cold and empty. Rather, it is a hugely dynamic environment with immense scale, structure and distant impact, with intergalactic oceans of highly energetic particles and energy fields forming space conditions. This review should be kept bedside for a lifetime.