Zond 6
Encyclopedia
Zond 6, a formal member of the Soviet Zond program
and unmanned version of Soyuz 7K-L1
manned moon-flyby spacecraft, was launched on a lunar flyby mission from a parent satellite (68-101B) in Earth parking orbit. The spacecraft, which carried scientific probes including cosmic ray
and micrometeoroid
detectors, photography equipment, and a biological payload, was a precursor to a manned circumlunar flight which the Soviets hoped could occur in December 1968, beating the American Apollo 8
.
Zond 6 flew around the moon on November 14, 1968, at a minimum distance of 2420 km. Photographs of the lunar near side and far side were obtained with panchromatic film. Each photo was 5 by. Some of the views allowed for stereo pictures. The photos were taken from distances of approximately 11,000 km and 3300 km. A skip reentry
of the spacecraft did not occur. Zond 6 landed in an undetermined region of the Soviet Union.
Zond 6 used a relatively uncommon technique called "skip reentry
" to shed velocity upon returning to Earth. A few hours before reentry, on November 17, 1968, a faulty O-ring
rubber gasket caused the cabin to depressurise, killing all biologicals aboard. Zond 6's parachutes also deployed too early and it crashed on Soviet soil. Only one negative was recovered from the camera container and a small victory obtained over the Americans. For propaganda reasons, the Soviets claimed the flight was a success, but they were not able to launch a manned flight to the Moon before Apollo 8
. A State Commission investigating the crash later determined that the coronal discharge effect which caused the parachute to jettison would only occur at the 25 mm capsule pressure. If the capsule had been completely depressurised to a high vacuum, the accident would not have occurred.
Zond 6 was the official designation for Soyuz 7K-L1
s/n 12. It was supposed to photograph the moon in colour and black and white from 8000 km and 2600 km ranges, then return to earth, landing at Tyuratam
only 16 km from the launch pad. It had been a long and difficult road to develop the L1 guidance system, but it worked perfectly that time.
This article was originally based on material from NASA (NSSDC) information on Zond 6
Zond program
Zond was the name given to two distinct series of Soviet unmanned space program undertaken from 1964 to 1970. The first series based on 3MV planetary probe was intended to gather information about nearby planets...
and unmanned version of Soyuz 7K-L1
Soyuz 7K-L1
The Soyuz 7K-L1 spacecraft was designed to launch men from the Earth to circle the Moon without going into lunar orbit in the context of the Soviet manned moon-flyby program in Moon race. It was based on the Soyuz 7K-OK with several components stripped out to reduce the vehicle weight...
manned moon-flyby spacecraft, was launched on a lunar flyby mission from a parent satellite (68-101B) in Earth parking orbit. The spacecraft, which carried scientific probes including cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...
and micrometeoroid
Micrometeoroid
A micrometeoroid is a tiny meteoroid; a small particle of rock in space, usually weighing less than a gram. A micrometeor or micrometeorite is such a particle that enters the Earth's atmosphere or falls to Earth.-Scientific interest:...
detectors, photography equipment, and a biological payload, was a precursor to a manned circumlunar flight which the Soviets hoped could occur in December 1968, beating the American Apollo 8
Apollo 8
Apollo 8, the second manned mission in the American Apollo space program, was the first human spaceflight to leave Earth orbit; the first to be captured by and escape from the gravitational field of another celestial body; and the first crewed voyage to return to Earth from another celestial...
.
Zond 6 flew around the moon on November 14, 1968, at a minimum distance of 2420 km. Photographs of the lunar near side and far side were obtained with panchromatic film. Each photo was 5 by. Some of the views allowed for stereo pictures. The photos were taken from distances of approximately 11,000 km and 3300 km. A skip reentry
Skip reentry
Skip reentry is a reentry technique involving one or more successive "skips" off the atmosphere to achieve greater entry range or to slow the spacecraft before final entry, which helps to dissipate the huge amount of heat that is usually generated on faster descents...
of the spacecraft did not occur. Zond 6 landed in an undetermined region of the Soviet Union.
Zond 6 used a relatively uncommon technique called "skip reentry
Skip reentry
Skip reentry is a reentry technique involving one or more successive "skips" off the atmosphere to achieve greater entry range or to slow the spacecraft before final entry, which helps to dissipate the huge amount of heat that is usually generated on faster descents...
" to shed velocity upon returning to Earth. A few hours before reentry, on November 17, 1968, a faulty O-ring
O-ring
An O-ring, also known as a packing, or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a disc-shaped cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface.The O-ring...
rubber gasket caused the cabin to depressurise, killing all biologicals aboard. Zond 6's parachutes also deployed too early and it crashed on Soviet soil. Only one negative was recovered from the camera container and a small victory obtained over the Americans. For propaganda reasons, the Soviets claimed the flight was a success, but they were not able to launch a manned flight to the Moon before Apollo 8
Apollo 8
Apollo 8, the second manned mission in the American Apollo space program, was the first human spaceflight to leave Earth orbit; the first to be captured by and escape from the gravitational field of another celestial body; and the first crewed voyage to return to Earth from another celestial...
. A State Commission investigating the crash later determined that the coronal discharge effect which caused the parachute to jettison would only occur at the 25 mm capsule pressure. If the capsule had been completely depressurised to a high vacuum, the accident would not have occurred.
Zond 6 was the official designation for Soyuz 7K-L1
Soyuz 7K-L1
The Soyuz 7K-L1 spacecraft was designed to launch men from the Earth to circle the Moon without going into lunar orbit in the context of the Soviet manned moon-flyby program in Moon race. It was based on the Soyuz 7K-OK with several components stripped out to reduce the vehicle weight...
s/n 12. It was supposed to photograph the moon in colour and black and white from 8000 km and 2600 km ranges, then return to earth, landing at Tyuratam
Tyuratam
Tyuratam is a station on the main Moscow to Tashkent railway, located in Kazakhstan. The name is a word in the Kazakh language and means "Töre's grave"; Töre, or more formally, Töre-Baba, was a noble, a descendant of Genghis Khan...
only 16 km from the launch pad. It had been a long and difficult road to develop the L1 guidance system, but it worked perfectly that time.
- Launch Date/Time: 1968-11-10 at 19:11:31 UTC
- On-orbit dry mass: 5375 kg
External links
This article was originally based on material from NASA (NSSDC) information on Zond 6