Kosmos 154 (russian: Космос 154 meaning ''Cosmos 154''), also known as L-1 No.3P, was a Soviet test spacecraft launched from the Baikonur aboard a

Proton-K The Proton-K, also designated Proton 8K82K after its GRAU index or SL-12 after its model number, 8K82K, was a Russian, previously Soviet, carrier rocket derived from the earlier Proton. It was built by Khrunichev, and launched from sites 81 an ...

rocket. It was a prototype Soyuz 7K-L1 launched by Proton. It was an uncrewed precursor to the Zond series.

History

The spacecraft was designed to launch a crew from the Earth to conduct a flyby of the Moon and return to Earth. The primary focus was a Soviet

circumlunar In orbital mechanics, a circumlunar trajectory, trans-lunar trajectory or lunar free return is a type of free return trajectory which takes a spacecraft from Earth, around the far side of the Moon, and back to Earth using only gravity once ...

flight, which help document the Moon, and also show Soviet power. The test ran from the Zond program from 1967-1970, which produced multiple failures in the 7K-L1's re-entry systems. The remaining 7K-L1s were scrapped, ultimately replaced by the

Soyuz 7K-L3 The Soyuz 7K-LOK, or simply LOK (russian: Лунный Орбитальный Корабль, translit=Lunniy Orbitalny Korabl meaning "Lunar Orbital Craft") was a Soviet crewed spacecraft designed to launch men from Earth to orbit the Moon, deve ...

Objectives

Two test flights of the UR-500K/L1 system were performed in March and April 1967 under the designations

Kosmos 146 Kosmos 146 (russian: Космос 146 meaning ''Cosmos 146''), also known as L-1 No. 2P, was a Soviet test spacecraft precursor to the Zond series, launched from the Baikonur Cosmodrome aboard a Proton K rocket. The spacecraft was designed to ...

and Kosmos 154. In April 1967, under the cover name Kosmos-154, the third model of the L-1 was placed into near-Earth orbit. Because of a control system failure that resulted in the premature jettisoning of the ullage motors, the main propulsion system of the Block-D did not ignite. Kosmos 154 was one of the first Zond attempts. It was supposed to flyby the Moon but achieved Earth orbit only.

Mission

Kosmos 154 was launched using a Proton-K carrier rocket, which flew from Site 81/23 at Baikonur. The launch occurred at 09:07 GMT on 8 April 1967. Kosmos 154 was operated in an Earth orbit, it had a perigee of , an apogee of , an inclination of 51.6° and an orbital period of 88.5 minutes. Kosmos 154 had a mass of . Kosmos 154 reached

Earth orbit Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Eart ...

but the

Blok D Blok D (russian: Блок Д meaning Block D) is an upper stage used on Soviet and later Russian expendable launch systems, including the N1, Proton-K and Zenit. The stage (and its derivatives) has been included in more than 320 launched r ...

translunar injection stage failed to fire (ullage rockets, which had to fire to settle propellants in tanks before the main engine fired, were jettisoned prematurely). Kosmos 154 burned up two days later when orbit decayed, on 10 April 1967.

Gallery

File:ZOND.jpg, An illustration of Zond spacecraft during trans-lunar coast. File:Zond L1 drawing-color.png, A color drawing of a Zond L1 spacecraft, the same type as Kosmos 154. File:The Soviet Union 1969 CPA 3733 stamp (Zond 5).png, A stamp from the Soviet Union in 1969 illustrating September 1968

Zond 5 Zond 5 (russian: Зонд 5, lit=Probe 5) was a spacecraft of the Soviet Zond program. In September 1968 it became the first spaceship to travel to and circle the Moon, the first Moon mission to include animals, and the first to return safely to ...

spacecraft lunar flyby. File:Stromgren Zond 8.jpg, A close-up image of the Moon taken by

Zond 8 Zond 8, also known as L-1 No.14, was the last in the series of circumlunar spacecraft, a member of the Soviet Zond program, designed to rehearse a piloted circumlunar flight, an uncrewed version of Soyuz 7K-L1 crewed circumlunar flight spacecr ...

in 1970.

References

{{Zond program Soviet space probes Zond program 1967 in the Soviet Union Spacecraft launched in 1967