ISIS Ionogram
ISIS/Alouette Topside Sounder
Restoration Project - Coverage on 35mm Film

Nearly 50 ground stations around the world have been used to collect Alouette/ISIS data. Ionograms on film are available from most of the stations for certain years. The type of coverage is illustrated for a sample of nine of these stations in Table 1. Table 1 lists the geographic location and the time spans covered by existing 35 mm films archived at the NSSDC. Detailed distributions of the available film data for each of these nine stations are available by clicking on the corresponding time interval in Table 1. If a station was closed before 1984, the closing date is indicated. Figure 1 shows the global location of the nine stations. The complete list of ground stations as given in the Report by J. Jackson (Alouette/ISIS Program Summary, NSSDC 86-09, Greenbelt, Maryland, Aug 1986) is shown in Table 2 (stations retired as of March 1984) and Table 3 (stations available as of March 1984).

A small percentage of Alouette/ISIS ionograms was converted into electron density profiles by various investigators (about 120 000 profiles) and submitted to NSSDC for archiving. These Alouette 1, 2, ISIS 1, 2 data sets are now available from SPDF's Anonymous ftp Archive

Go to the ISIS/Alouette Data Restoration Home Page

For more information about this project, please contact Dieter Bilitza at