James Van Allen, astrophysicist and space pioneer for whom the Van Allen radiation belts are named, was among the principal scientific investigators for 24 space missions. Foerstner, who teaches science writing in the graduate program at Northwestern University's Medill School of Journalism and a former science reporter for the Chicago Tribune, drew on the astrophysicist's correspondence and publications, as well as interviews with more than 100 other scientists, for this biography.