Other Free Encyclopedias » Science Encyclopedia » Science & Philosophy: Two-envelope paradox to Venus » Van Allen Belts - Discovery Of The Radiation Belts Of Earth, Description, Related Geophysical Effects, Radiation Belts Of Other Planets - Artificial radiation belts, Limitations on space flight, Two common misperceptions

Van Allen Belts - Discovery Of The Radiation Belts Of Earth

explorer instrument including iowa

The first successfully launched American satellite of Earth was Explorer I. It was propelled into orbit from Cape Canaveral, Florida, on January 31, 1958, by a four-stage combination of rockets developed by the United States Army Ballistic Missile Agency and the Jet Propulsion Laboratory (JPL). The principal scientific instrument within the payload was a Geiger tube radiation detector developed by Professor James A. Van Allen and graduate student George H. Ludwig of the University of Iowa. The instrument's intended purpose was a comprehensive survey of cosmic ray intensity above Earth's atmosphere.

The launch of an improved version of the radiation instrument was attempted on March 5 on Explorer II, but an orbit was not achieved because the fourth stage rocket failed to ignite. On March 26, the launch of the improved instrument on Explorer III, including the first magnetic tape recorder ever flown in space, was successful.

The in-flight data from the radiation detectors on Explorer I and Explorer III revealed that there are enormous numbers of energetic, electrically charged particles trapped in the external magnetic field of Earth. This discovery was promptly confirmed and extended later in 1958 with additional space flights by the Iowa group and others, including Soviet investigators on Sputnik III. In subsequent years the continuing study of this phenomenon has included the efforts of over 1000 scientists in at least 20 different countries.


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over 8 years ago

I am trying to get information on an Van Allen Radiation Belt experiment That was flown on a Mercury sub orbital flight mid 1960s. This device designed built by Science Systems, Div. of Industro Transistor Corp. consisting of two G,M,Tubes and a signal conditioning module. I was involved in the design of this experiment for NASA -JPL, but unable to find any record of it's existance. The mock-up was shown on TV the morning of the flight. Do you know where I could find a record of this experiment?