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Cosmic Ray

NSSDC ID: 1958-003A-01
Mission Name: Explorer 3
Principal Investigator: Prof. James A. Van Allen


A halogen-quenched anton-type Geiger-Mueller counter that measured the total omnidirectional cosmic-ray intensity was used to study the arrival of primary cosmic radiation on a comprehensive geographical and temporal basis. In addition to real-time data transmission, a tape recorder memory system was used to store a 6-sec averaged counting rate of data acquired. On radio command, the unit transmitted averaged data for an entire orbit. Data were used to aid in outlining the belt of high-intensity radiation at altitudes about 700 km discovered by Explorer 1. This unforeseen high-intensity band saturated the Geiger-Mueller counter. The instrumentation performed well for 44 days. Continuous data were provided until May 10, 1958 and data were transmitted on command until May 14, 1958.


  • Space Physics: Heliospheric Studies

Additional Information

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NameRoleOriginal AffiliationE-mail
Prof. Louis A. FrankOther InvestigatorUniversity of
Prof. James A. Van AllenPrincipal InvestigatorUniversity of Iowa 
Dr. George H. LudwigOther InvestigatorNOAA National Environmental Satellite, Data and Information Service 
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