Molniya-M

The Molniya-M, with the GRAU index 8K78M, was a Soviet and Russian launch vehicle derived from the R-7 Semyorka intercontinental ballistic missile. It improved on the original 8K78 booster, which had been the product of a rushed development programme and had failed ten times in its first twelve launches by the end of 1962: the core and strap-ons received up-rated engines, the third stage was completely redesigned and the upper stage engine was slightly enhanced. The 8K78M first flew on 4 October 1965, when it launched Luna 7, and it made 297 launches with 21 failures. Although developed for planetary probes, which moved to the larger Proton booster by the 1970s, for most of its life it launched Molniya communications satellites and Oko early warning satellites into Molniya orbits, highly eccentric orbits that let a satellite dwell over polar regions. There were four main variants, differing in their upper stage: Blok-L, Blok-2BL, Blok-ML and Blok-SO-L. The final flight lofted an Oko satellite from Plesetsk on 30 September 2010, after which the Russian Space Forces confirmed it had been retired from service, replaced by the Soyuz-2 with the Fregat stage. The Progress Rocket Space Centre lists it among the rockets it built.