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Positive Ion Composition

NSSDCA ID: 1967-073A-16

Mission Name: OGO 4
Principal Investigator:Mr. Harry A. Taylor, Jr.


The specific objectives of this experiment included (1) a study of the ion composition as a function of magnetic coordinates (latitude, longitude, time, and McIlwain's L parameter) to investigate the means and degree of magnetic control of the ion distribution, (2) a comparison of measurements obtained from the same experiment on both the POGO and EOGO spacecraft, with special attention given to ionic diffusion along L shells, and (3) a study of the temporal, solar, and geomagnetic effects on the ion distribution and transition levels. A ceramic Bennett radio-frequency ion mass spectrometer tube with its associated electronics was used to measure thermal atmospheric ions having mass-to-charge ratio values from 1 to 45, with a mass resolution of about 1 in 20 u. Concentrations from 10 to 1.E6 ions/cc could be measured. The time between consecutive samples of each ion detected, i.e., the spectral sweep rate, was 25.6 s, a time interval corresponding to a spatial resolution of from 175 to 200 km along orbit path, or to 1.5 deg in latitude. The instrument was mounted in the orbital plane experiment package.

Alternate Names

  • OGO4/PositiveIonComposition


  • Space Physics: Ionospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Dr. Nelson W. SpencerOther InvestigatorNASA Goddard Space Flight Center
Mr. Harry A. Taylor, Jr.Principal InvestigatorNASA Goddard Space Flight Center
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