The USSR launched Zond 5, the first spaceship to orbit the moon and reenter Earth’s atmosphere, on this day, i.e, September 15, in 1968. According to NASA, the spaceship was launched from a Tyazheliy Sputnik in Earth parking orbit to make scientific studies during a lunar flyby and to return to Earth. Two days after the launch, on September 18, Zond 5 flew around the Moon and the closest distance was noted to be 1,950km.
Zond 5 was the 11th mission for the UR-500 rocket series and the seventh launch of the UR-500K variant equipped with Black D. A biological payload of turtles, wine flies, mealworms, plants, seeds, bacteria and other living matter was also included in the flight. Additionally, the Russia Academy of Science had informed that in the pilot’s seat was a 175cm tall, 70kg mannequin containing radiation detectors.
The spacecraft was able to take high-quality photographs of the Earth at a distance of 90,000km. According to NASA, en route to Moon, the main stellar attitude control optical surface became contaminated and was rendered unusable. While returning to Earth, another attitude control sensor failed, making the planned guided entry onto Soviet territory impossible and forcing the spacecraft controllers to use a direct ballistic entry.
1st successful USSR circumlunar Earth-return mission
On September 21, 1968, the reentry capsule entered the Earth’s atmosphere, braked aerodynamically, and deployed parachutes at 7km. The capsule splashed down in the backup area in the Indian Ocean and was successfully recovered, safely returning the biological payload.
It was reported, the turtles had lost 10 per cent of their body weight but remained active and showed no loss of appetite. Zond 5 was planned as a precursor to crewed lunar spacecraft. It represented the first successful USSR circumlunar Earth-return mission. Back then, the transmissions of astronauts calling out readings of instruments from the spacecraft were received at Jodrell Bank, this led to the conclusion that cosmonauts at Yevpatoriya were relaying reports through the spacecraft as a training exercise, as was done on Zond 4.