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Summary Spectrograms on Microfiche


Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)

Time span: 1977-10-22 to 1983-08-05


This data set contains 3-h summary spectrograms plus other experiment, ephemeris, and plasma information on each frame of microfiche. Each frame displays four panels of information. The lowest two panels are spectrograms using grey scales of 10 3-dB steps to display the average power received by the sounder as a function of time and of the sounder's 128 frequency steps with center frequencies ranging from 0.5 to 50.7 kHz. The two spectrograms plot the same data using grey scales covering different ranges. The value of the top of the scale used in the upper spectrogram and the value of the bottom of the scale used in the lower spectrogram are given in the boxes marked MAX and MIN on the left side of each frame. The ranges of these scales change with time. Immediately above the spectrograms is a panel that gives a summary presentation of data from the propagation experiment, including the mean electron density in each 32-s period, the rms fluctuation of the density, and the electron gyrofrequency obtained from the data pool tape or a magnetospheric model. The top panel contains experiment status information (sounder step duration, frequency step, and antenna used) as indicated in the square box to the left. Ephemeris information on the left side of each frame include B and L coordinates, magnetic local time, magnetic latitude, ecliptic local time, the geocentric radial distance and GSE coordinates in Re, and the ISEE 1 - ISEE 2 separation distance in km. The two sets of values correspond to the beginning and the end of the 3-h interval. Data set users should consult the more detailed description found in C. C. Harvey et al., Early Results from the ISEE Electron Density Experiment, Space Science Review, vol. 23, pp. 39-58, March 1979.

Alternate Names

  • Summary Spectrograms, Mfiche


  • Space Physics: Magnetospheric Studies
  • Space Physics: Heliospheric Studies


  • 77-102A-08F

Additional Information



Questions and comments about this data collection can be directed to: Dr. H. Kent Hills



NameRoleOriginal AffiliationE-mail
Dr. Christopher C. HarveyGeneral ContactObservatoire de Paris,
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