225 



U.S.S.R. 



IK 5 : December 2, 1971, studied charged particles and 



low frequency electromagnetic waves. Czecho- 

 slovakia and the U.S.S.R. provided the equipment. 

 There were participating tracking stations In 

 Czechoslovakia, the U.S.S.R., and the Democratic 

 Republic of Germany. 



IK 6 : April 7, 1972, studied the chemical composition 



and energy spectrum of cosmic rays. The equip- 

 ment was made In the U.S.S.R. according to 

 specifications made in Hungary, Mongolia, Poland, 

 Romania, Czechoslovakia, and the U.S.S.R. A 

 meteorite experiment was developed and manufac- 

 tured in Hungary, Czechoslovakia, and the U.S.S.R. 



IK 7 : June 30, 1972, continued short-wave radiation 



and hard x-ray studies. It observed solar 

 flares not seen from Earth stations. It carried 

 equipment from the Democratic Republic of Ger- 

 many, Czechoslovakia, and the U.S.S.R. 



IK 8 : December 1, 1972, the satellite carried equip- 



ment from Bulgaria, the Democratic Republic of 

 Germany, Czechoslovakia, and the U.S.S.R. The 

 first IK satellite was launched from Plesetsk, 

 where specialists from participating Eastern 

 Bloc countries observed the launch. 



IK-9/K0PERNIK 500 : April 19, 1973, measured solar radiation and the 



ionosphere. It also commemorated the 500th 

 birthday of Copernicus. The equipment was 

 Polish, Czechoslovaklan and Soviet. The data 

 were received at ground stations in the U.S.S.R. 

 and Czechoslovakia. 



IK-10 : October 30, 1973, the payload carried East German 



and Soviet equipment to determine the concentra- 

 tion and temperature of ionospheric electrons, 

 Soviet apparatus to measure magnetic field 

 variation, and Czechoslovaklan equipment to 

 study low-frequency electric oscillation of 

 plasma. 



IK-11 : May 17, 1974, measured solar ultraviolet and 



x-ray radiation in the upper atmosphere of 

 Earth. The experiments were provided by the 

 Democratic Republic of Germany, the U.S.S.R., 

 and Czechoslovakia. 



