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9-second/18-second Electron Moments (N, V, T, H)


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

Time span: 1977-10-27 to 1978-12-31


These data consist of experimenter-supplied electron moments from the Vector Electron Spectrometer on ISEE-1. Each data record consists of the year, day of year (January 1 = Day 0), milliseconds of day, the geocentric radius of the spacecraft location, spacecraft position in GSE coordinates, the electron density (cm^-3), electron temperature (degrees K), parallel-to-perpendicular temperature anisotropy, GSE components of the bulk flow velocity (cm/sec), GSE components of the heat flux vector (erg cm^-2 sec^-1), GSE components of the magnetic field from the Pool magnetometer data (nT), and the spacecraft potential (eV). The time corresponds to the start of the data collection interval, i.e., the start of the spin. The time between data records is approximately 9.12 seconds or 18.24 seconds depending on the bit rate. This is because although data are collected over a single 3-second spin, data are then read out over a multiple spins. Since the magnetic field data are at a resolution of 64 seconds, the same magnetic field record was used multiple times; no interpolation was done on the magnetic field data values. The electron temperature value is derived from one-third of the trace of the pressure tensor, i.e., it is equal to [T(parallel) + 2*T(perpendicular)]/3.

Alternate Names

  • 9S/18S Electron Moments(N,V,T,H)


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


  • 77-102A-02D

Additional Information



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



NameRoleOriginal AffiliationE-mail
Mr. Franklin W. OttensData ProviderNASA Goddard Space Flight
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