INTERCOSMOS 19

The Intercosmos-19 satellite was designed for investigations of the topside ionosphere structure and electromagnetic processes in it.

        It was launched on February 27, 1979 and worked over 3 years (till April, 1982). Its apogee and perigee were equal to 995 km and 502 km correspondingly, the orbit inclination was about 74^o, the revolution period about 100 min, the distance between consecutive crossings the equator was near 25^o in longitude. The local time of these crossings changed roughly by 1 hour during 5 days.

        Local time of Intercosmos-19 crossings the geographic equator is shown in the figure:

        The instruments installed onboard Intercosmos-19 were designed and manufactured by scientists of Bulgaria, Poland, Czechoslovakia and USSR. The Intercosmos-19 scientific equipment included the topside sounder IS-338 (USSR), Langmuire probe P-4 (Bulgaria, USSR), local temperature probe KM-3 (USSR, Czechoslovakia), photometer EMO-1 (Bulgaria), soft particle spectrometer SF-3 (USSR), differential high energy spectrometer Perot-3 (USSR), VLF analyser ANCh-2ME (USSR, Czechoslovakia), HF wideband receiver with wideband telemetry transmitter AVCh-2 (USSR), ionospheric radoispectrometer IRS-1 (Poland), coherent 3-frequency beacon transmitter M4K-3 (Czechoslovakia).

        The digital topside sounder IS-338 worked from March 5, 1979 to April 8, 1982. It had the frequency band 0.3 to 15.95 MHz. The sounding data could be directly transmitted to a receiving station (direct mode) or be stored in the onboard memory device for a certain period and then sent to the Earth (recording mode). Three recording modes were used: 2, 3, and 4. At mode 2 the time between two consecutive ionograms (sampling period) was 8 s and the data storage period was near 30 min, at modes 3 and 4 the sampling periods were 16 and 64 s, and the storage periods were near 2 and 16 hours correspondingly. The details of the sounder work can be found in the book "Аппаратура для исследования внешней ионосферы. ИЗМИРАН. М. 1980" (in Russian). The catalogue of the sounder work periods is attached to this Database.

        Data for many of these periods have been treated, and a lot of interesting findings were made which were described in a great number of papers (see Bibliography). But extracting the data of a specific device from the original telemetry information received from the satellite and stored on magnetic tapes is a very laborious, multistep, and expensive process, so considerable number of periods is not treated up to now.

        In the presented Database, data obtained by only one of these devices were used - the digital topside sounder IS-338 designed and made in IZMIRAN in cooperation with Special Constructor Bureau (Troitsk, Russia). The Intercosmos-19 sounder worked from March 5, 1979 to April 8, 1982. The Cosmos-1809 sounder worked from January 15, 1 987 to May 22, 1993.

       The Database allows you to get topside electron density profiles for chosen time periods within these intervals.

You may submit questions of a technical nature to developers.