Explorer I, Reel 2146, March 6, 1958 by _SPACE_audio published on 2015-10-09T18:58:44Z This is a sample from the first US orbital spacecraft, Explorer 1, which carried an instrument designed and built by Professor J. A. Van Allen's research group at The University of Iowa. You are hearing the voice-annotated recording of the encoded data signal as received on the ground. Genre space