The Luna 8K72 vehicles were carrier rockets used by the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

for nine

space probe Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which th ...

launch attempts in the

Luna programme The Luna programme (from the Russian word "Moon, Luna" meaning "Moon"), occasionally called ''Lunik'' by western media, was a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. The programme acc ...

between 23 September 1958 and 16 April 1960. Like many other Soviet launchers of that era, the Luna 8K72 vehicles were derived from the

R-7 Semyorka The R-7 Semyorka (, GRAU index: 8K71) was a Soviet Union, Soviet missile developed during the Cold War, and the world's first intercontinental ballistic missile. The R-7 made 28 launches between 1957 and 1961. A derivative, the R-7A Semyorka, R ...

design, part of the R-7 (rocket family), which was also the basis for the Vostok and modern Soyuz rocket. The 8K72 was the first R-7 variant explicitly designed as a carrier rocket and it incorporated a few features that became standard on all later R-7 carrier rockets including thicker tank walls to support the weight of upper stages and the AVD malfunction detection system, which would terminate engine thrust if the booster's operating parameters (engine performance, electrical power, or flight trajectory) deviated from normal.

Launches

Luna 8K72 was launched nine times from Baikonur LC-1/5: The first flight of a Luna 8K72 (September 1958), which was to launch the Luna E-1 No.1 probe, ended 92 seconds after launch when the rocket broke up from longitudinal ("pogo") oscillations, causing the strap-ons to separate from the vehicle, which then crashed downrange. The second flight of a Luna 8K72 (October 1958), which was to launch the Luna E-1 No.2 probe, ended 104 seconds after launch when the rocket again disintegrated from vibration. The third flight of a Luna 8K72 (December 1958), which was to launch the Luna E-1 No.3 probe, ended 245 seconds after launch when the Blok A core stage shut down from loss of engine lubricant. The resonant vibration problem suffered by the 8K72 booster was the cause of a major argument between the Korolev and Glushko design bureaus. It was believed that the vibrations developed as a consequence of adding the Blok E upper stage to the R-7, shifting its

center of mass In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weight function, weighted relative position (vector), position of the d ...

. The first probe launched by a Luna 8K72 to reach orbit was

Luna 1 ''Luna 1'', also known as ''Mechta'' ( , ''Literal translation, lit.'': ''Dream''), ''E-1 No.4'' and ''First Lunar Rover'', was the first spacecraft to reach the vicinity of Earth's Moon, the first spacecraft to leave Earth's orbit, and the fi ...

, launched on 2 January 1959, which was intended as a lunar impactor mission. Luna 1 instead passed within of the Moon's surface 4 January 1959, and then went into orbit around the Sun between the orbits of Earth and Mars. The fifth flight of a Luna 8K72 (18 June 1959), which was to launch the Luna E-1A No.1 probe, ended 153 seconds after launch due to a guidance malfunction of the Blok A core stage, leading to engine shutdown. Luna 2 was launched by a Luna 8K72 on 12 September 1959. It was the first spacecraft to impact the lunar surface. The final successful launch of a Luna 8K72 took place on 4 October 1959. The

Luna 3 Luna 3, or E-2A No.1 (), was a Soviet spacecraft launched in 1959 as part of the Luna programme. It was the first mission to photograph the far side of the Moon and the third Soviet space probe to be sent to the neighborhood of the Moon. The hi ...

spacecraft took the first photographs of the far side of the Moon. The eighth flight of a Luna 8K72 (March 1960), which was to launch the Luna E-3 No.1 probe, ended 435 seconds after launch when the Blok E upper stage developed insufficient thrust, causing the Luna probe to reenter the atmosphere and burn up. The ninth flight of a Luna 8K72 (April 1960), which was to launch the Luna E-3 No.2 probe, failed when the Blok G strap-on booster developed only 75% thrust at liftoff, breaking away from the launch vehicle, which then disintegrated, the strap-ons flying in random directions and exploding as they impacted the ground. The Blok A core stage then crashed into a salt lake.

References

{{R-7 rockets 1958 in spaceflight 1959 in spaceflight

rocket A rocket (from , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely ...

Space launch vehicles of the Soviet Union R-7 (rocket family)