Molniya (rocket)

Molniya (R-7 8K78)

Molniya-M carrier rocket
Function	Medium launch vehicle
Manufacturer	Energia
Country of origin	Soviet Union
Size
Height	43.44 m
Diameter	10.3 m
Mass	305,000 kg
Stages	4
Associated rockets
Family	R-7
Launch history
Status	Retired
Launch sites	Baikonur, Plesetsk
[edit on Wikidata]

The Molniya (Russian: Молния, meaning "lightning"), GRAU Index 8K78, was a modification of the well-known R-7 Semyorka rocket and had four stages.^[1][2] The rocket was given the name Molniya due to the large number of Molniya communication satellites the rockets launched. ^[3]

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 basic R-7 core was also structurally strengthened and given more powerful engines.

A rushed development produced multiple malfunctions of the upper stages, which led to its being replaced by the improved Molniya (M) in 1964, but there were enough 8K78s left to continue flying them into 1967.^[4][5][6][7] The Molniya also carried early Venera probes to Venus.^[2]

Molniya (E6) was a minor revision adapted for launch of some Luna series space probes.^[2]