NSSDCA ID: SPIO-00095
Availability: At NSSDC, Ready for Electronic Access
Time span: 1971-04-01 to 1984-01-27
This collection consists of ISIS 2 ionograms that have been obtained through an AISRP-funded data restoration project. The ISIS ionograms (consisting of a fixed-frequency and a swept-frequency part) were digitized from the original ISIS telemetry tapes. Detailed information about the project can be found at: http://nssdc.gsfc.nasa.gov/space/isis/isis-status.html
The digitized sounder data (consisting of 8-bit receiver-amplitude values collected at a 40 kHz rate) contain the time and the frequency associated with each sounder pulse. The frequency of each sounder pulse is determined from a 3rd degree interpolation between the times of the frequency markers as identified in the sounder video during the A/D operation. This data set contains the average-resolution ionograms (averages of each 4 successive 40 kHz 8-bit values) in the PI-provided OS2 binary format. Other related data sets archived include: (1) the full resolution ionograms in OS2 binary; (2) the average resolution ionograms in CDF format; (3) ASCII header files with pass-specific information; and (4) the PCM data which contain header, time, AGC, frequency-marker information and telemetry-level data from all other ISIS-2 instruments. The ASCII header files are also available from: https://spdf.gsfc.nasa.gov/pub/data/isis/topside_sounder/
The CDF data are available for plotting and downloading on CDAWeb at: http://cdaweb.gsfc.nasa.gov/cdaweb/sp_phys/
A search page http://nssdc.gsfc.nasa.gov/space/isis/isis_menu4.html lets users locate data for specified dates, times, locations and other search criteria.
ISIS-2 data are available to the extent permitted by telemetry station scheduling and the location of telemetry stations. The data selected for the ISIS data restoration effort include data from 24 telemetry stations. A list of stations can be found at: http://nssdc.gsfc.nasa.gov/space/isis/isis-table1-new.html Their location on a worldmap is shown in: http://nssdc.gsfc.nasa.gov/space/isis/isis_station_lar.GIF
This collection is available on-line in the directory ionogram_os2bin at: https://spdf.gsfc.nasa.gov/pub/data/isis/topside_sounder/
Questions and comments about this data collection can be directed to: Dr. Dieter K. Bilitza
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Robert F. Benson | General Contact | NASA Goddard Space Flight Center | rbenson@pop600.gsfc.nasa.gov |