“…In this Commentary, we discuss what space physics is, its societal relevance and its impact on U.S. policy. A number of pieces have been written about the related topic of space weather [ Baker , ; Baker and Lanzerotti , ] and its societal and policy impacts [ Fry , ; Lanzerotti , ; Schrijver , ; Jonas and McCarron , ; Cassak , ; Gaunt , ; Bonadonna et al , ]; the emphasis for this Commentary is the broader field of space physics.…”