Document Type


Peer Reviewed


Publication Date


Journal/Book/Conference Title

Review of Scientific Instruments

DOI of Published Version



The first U. S. satellite, 1958 Alpha (Explorer I) carried instrumentation to measure cosmic-ray intensity, micro-meteorite. impacts, and temperatures within the satellite. The instrumentation was designed with emphasis on conservation of electrical power, on stable and reliable operation, on operation over a wide range of temperatures, and on compactness and mechanical ruggedness. The cosmic-ray instrumentation in 1958 Alpha operated according to expectations, providing several hundred recordings of data received during transits over ground stations. These data led to the discovery of a belt of high intensity radiation around the earth.

Published Article/Book Citation

The definitive version was published in Review of Scientific Instruments 30, 223 (1959). doi: 10.1063/1.1716522


© 1959 The American Institute of Physics. This article is posted here by permission of AIP for personal use, not for redistribution.