The Injun program was a series of six satellites designed and built by researchers at the University of Iowa. They were intended to observe various radiation and magnetic phenomena in the ionosphere and beyond. In spite of various hardware difficulties and the loss of Injun 2 due to an upper stage failure, the program was generally successful. In particular they produced data on the Van Allen radiation belts including electrical convection in the magnetosphere and the radiation after effects of the Starfish Prime high-altitude nuclear test.