Sputnik 3 Satellite
Sputnik 3 was a Soviet satellite launched on 15 May 1958 from Baikonur Cosmodrome by a modified R-7/SS-6 ICBM. The scientific satellite carried a large array of instruments for geophysical research of the upper atmosphere and near space.
In July 1956, the Soviet Union’s OKB-1 completed the preliminary design for the first Earth satellite, designated ISZ (Artificial Earth Satellite). ISZ was known to its designers as “Object D” with the name deriving from the plan that it would be the 5th object built for the R-7 missile to carry. Design of Object D had begun in January 1956 with intent to launch it during the International Geophysical Year. Object D was planned to be the first satellite launched by the Soviet Union but ended up being the third following delays due to problems developing the extensive scientific experiments and their telemetry system.