50 years ago, the Soviet Union test launched the R-7, the world’s first ICBM. It’s design of parallel expendable boosters was devised by the mathematician D.E. Okhotsimsky, who considered a variety of schemes for maximizing the range of a rocket by ejecting portions of its construction during flight.

Seen above left is one of the first test launches of the ICBM. To the right is a modern Soyuz rocket, with its additional sequential stages. The R-7 was capable of placing the 1.3 ton Sputnik-3 satellite into orbit. The modern Soyuz with its additional stages can place 7.4 tons into low Earth orbit.

With 50 years of use and about 1700 missions, the R-7 family is arguably one of the most important rockets in the history of space exploration.