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Alouette 1 Topside Sounder CRC, Electron Density Profiles, 1962-66 (ASCII)


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

Time span: 1962-09-29 to 1966-03-30


This data set, prepared by the Communications Research Centre in Ottawa, Canada, consists of electron density profiles for the ionosphere above the F2 maximum (topside ionosphere). The data set is in chronological order, and it includes about 43,000 profiles obtained primarily during the period 1962 to 1965. The profiles were computed from digital values of frequency and virtual height that were scaled from ionograms. Profile data consist of electron density and real height values for each point scaled from the ionogram. Telemetry stations are not identified, but satellite location, time of observation (Greenwich and local mean time), solar zenith angle at the satellite, magnetic dip and gyrofrequency at the satellite, total electron content down to lowest topside reflection altitude, and other relevant information are listed for each profile. These profiles correspond to about 2% of the 2.E6 Alouette 1 ionograms observed. Data for most latitudes are included, but those data from longitudes near 80 degree West are more numerous than those from other longitudes. The data were originally provided on 9-track, 1600-bpi, odd-parity, EBCDIC tape written on a MODCOMP-4 computer. NSSDC prepared an ASCII version that is available on-line at: under directory /crc_ne_profile_ascii/.

Alternate Names

  • AL-1,CRC Ne Profiles, ASCII, online


  • Space Physics: Ionospheric Studies


  • 62-049A-01T

Additional Information



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



NameRoleOriginal AffiliationE-mail
Dr. J. H. WhittekerData ProviderDepartment of Communications/Communications Research Centre

Selected References

  • Alouette 1 (1962 Beta Alpha 1) topside sounder, NASA-GSFC, NSSDC 67-29, Greenbelt, MD, July 1967.
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