Zond 5
The Soviet Union launched Zond 5 on the 14th of September 1968. This mission followed a string of failures in their lunar program. Three previous circumlunar attempts had failed or resulted in partial success. A launch failure occurred on the 23rd of April when an erroneous abort command shut down the Proton rocket's second stage. Another explosion happened in July that killed three people on the launchpad. These disasters created immense pressure to succeed before sending humans into space. The political stakes were incredibly high during the height of the Cold War. American intelligence agencies watched every move with intense scrutiny. The Soviets needed to prove their technology worked without risking cosmonaut lives. They decided to send animals instead for this uncrewed test flight.
Two Russian tortoises named Chertan and Malysh flew aboard the spacecraft. Each animal weighed approximately 0.7 kilograms before the journey began. Scientists chose these reptiles because they could be tightly secured inside the vehicle. Alongside the tortoises, fruit fly eggs traveled through the vacuum of space. Wheat, barley, pea, pine, carrots, and tomato cells also made the trip. Specimens of the wildflower species Tradescantia paludosa accompanied the other biological samples. Three strains of single-celled green algae called Chlorella completed the living cargo. One strain of lysogenic bacteria was included as well. Soviet scientists selected extremophiles with higher radioresistance than typical human cells. This choice meant the results would not directly translate to human physiology. The food deprivation started twelve days before launch for both space-bound and control groups.
The Proton-K carrier rocket lifted off from Site 81 at Baikonur Cosmodrome. Heat caused interior coating to outgas during the ascent phase. This contamination delayed an attitude correction maneuver on the way to the Moon. A contaminated star tracker caused the spacecraft to deviate from its planned path. On the 18th of September, the craft flew around the Moon without entering orbit. The closest approach distance reached only 1,960 kilometers instead of the intended closer range. Another star tracker failed during the return journey home. The spacecraft erroneously switched off the guided reentry system entirely. Eight ships were deployed to the Indian Ocean prior to launch as a precaution. Only three of those vessels carried rescue helicopters onboard. The deviation forced an emergency splashdown far from the primary landing zone in Kazakhstan.
The reentry capsule splashed down in the Indian Ocean on the 21st of September. Nighttime conditions impaired recovery efforts significantly. The capsule landed approximately 350 kilometers from the nearest Soviet naval ship. Two vessels named Borovichy and Vasiliy Golovnin retrieved the spacecraft. It took ten hours to bring the biological specimens aboard one of the ships. American shadowing occurred during the operation but ceased once the capsule was secured. The entire journey lasted six days, eighteen hours, and twenty-four minutes. High-quality photographs taken at a distance of 1,960 kilometers became the first of their kind. British astronomer Bernard Lovell stated that the mission showed Soviets were ahead in space technology. The British Interplanetary Society believed crewed lunar flights could happen within months.
Tortoise Chertan lost 10% of its body weight during the trip. Tortoise Malysh also experienced similar weight loss over the same period. Control tortoises lost only 5% of their weight under identical fasting conditions. Dissection occurred on the 11th of October after thirty-nine days of starvation. Blood analysis revealed no differences between space-traveling tortoises and control specimens. Flying tortoises had elevated iron and glycogen levels in their livers. The flight affected internal structures of their spleens as well. Scientists concluded these changes resulted primarily from starvation rather than space travel itself. The animals showed no loss of appetite despite the long duration. Soviet officials announced the flight carried living animals in November 1968. This announcement came one month before the planned Apollo 8 flight to demonstrate capability.
On the 19th of September 1968, voices appeared to come from the spacecraft. Jodrell Bank Observatory and the CIA intercepted transmissions claiming cosmonauts were aboard. Valery Bykovsky, Vitaly Sevastyanov, and Pavel Popovich spoke about telemetry data. They discussed making an attempt to land on the lunar surface. Engineers linked the probe receiver to a transmitter with a jumper wire. Popovich recorded himself saying the flight proceeded according to normal while approaching the surface. His voice traveled back to Earth including reception by American agencies. President Johnson called Frank Borman asking why Popovich was reporting from the moon. Borman later met Popovich at an airport where he shook his fist in anger. Eugene Cernan remarked that the incident shocked everyone involved. The hoax created real turmoil within U.S. intelligence circles during the height of the Cold War.
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Common questions
When did the Soviet Union launch Zond 5?
The Soviet Union launched Zond 5 on the 14th of September 1968. This mission followed a string of failures in their lunar program.
Which animals flew aboard Zond 5 during the 1968 spaceflight?
Two Russian tortoises named Chertan and Malysh flew aboard the spacecraft. Each animal weighed approximately 0.7 kilograms before the journey began.
Where did the Zond 5 reentry capsule splash down after returning from the Moon?
The reentry capsule splashed down in the Indian Ocean on the 21st of September. Nighttime conditions impaired recovery efforts significantly.
What happened to the tortoises Chertan and Malysh after the Zond 5 mission ended?
Tortoise Chertan lost 10% of its body weight during the trip while Tortoise Malysh also experienced similar weight loss over the same period. Dissection occurred on the 11th of October after thirty-nine days of starvation.
Why did American intelligence agencies intercept transmissions claiming cosmonauts were aboard Zond 5?
On the 19th of September 1968, voices appeared to come from the spacecraft which Jodrell Bank Observatory and the CIA intercepted as claims that cosmonauts were aboard. The hoax created real turmoil within U.S. intelligence circles during the height of the Cold War.