The Molniya 8K78 (Russian: Молния, meaning "lightning") was a modification of the well-known R-7 Semyorka rocket and had four stages.
The 8K78 resulted from a crash program by the Korolev Bureau to develop a booster for launching planetary probes. A larger third stage was added along with a fourth stage (Blok L) that was designed to fire in-orbit to send the payload out of LEO. The early launches in 1960-62 suffered multiple malfunctions of the upper stages, which led to its being replaced by the improved Molniya M in 1964.
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