Space Soviet Endeavours to The Moon

Night launch of the Zond 5 from the Baikonur Cosmodrone. based upon a picture RKK Energiya

The Lunas

Soon after the opening of the Space Age, both the Soviet Union and the United States set their sights on the Moon as a target for exploration by robotic spacecraft. In March 1958, the Soviet Union approved the development of one series of spacecraft to impact the Moon’s surface and another to photograph the Moon’s hidden far side during a flyby

The first three Soviet attempts to reach the Moon in 1958 ended in launch failures caused by various anomalies with the R-7 rocket. On Jan. 2, 1959, the Soviet Union announced the launch of their first Cosmic Rocket -- retroactively renamed Luna 1 in 1963 -- carrying a spherical spacecraft with six scientific experiments (space radiation, magnetic fields, and micrometeorite impacts). The launcher's upper stage however fired longer than planned, and the probe missed the Moon by about 4,000 miles, 34 hours after launch. On the way to the Moon, the upper stage released one kilogram of sodium gas at a distance of 74,000 miles, creating a cloud that Soviet ground-based astronomers were able to photograph. Luna 1, 62 hours after the Moon flyby, entered solar orbit, being the first spacecraft to do so. Following another launch failure in June 1959, the Soviets launched their second Cosmic Rocket (later renamed Luna 2) on Sep. 12 and it successfully achieved escape velocity and placed the spacecraft, virtually identical to Luna 1, on an intercept course with the Moon. The upper stage once again released its one kilogram of sodium gas at a distance of 97,000 miles. On Sep. 13, Soviets reached their first lunar success as Luna 2 became the first spacecraft to make contact with another celestial body when it impacted the Moon between Mare Imbrium and Mare Serenitatis (that was about 160 miles from where Apollo 15 would land 12 years later). No magnetic field or radiation belts were spotted around the Moon as Luna 2 deposited Soviet emblems on the lunar surface, carried in two metallic spheres. A copy of a sphere was presented by Soviet Premier Nikita S. Khrushchev to President Dwight D. Eisenhower

The Russian photography missions, as far as they were concerned, achieved success on their first attempt. The Automatic Interplanetary Station (future Luna 3) launched on Oct. 4, 1959. It was also carrying instruments about radiation levels and micrometeorite impacts. It passed on Oct. 6 over the Moon’s southern polar region at an altitude of 4,900 miles before looping behind the Moon. The next day, at a distance of 40,500 miles, Luna 3 began taking 29 photographs of the Moon’s far side and the film was developed onboard the spacecraft and scanned much like a facsimile before the images were transmitted to Earth. The Luna 3 photographed about 70 percent of the Moon’s far side with a quality rather poor. A distinctly different appearance than the Earth-facing side was revealed however, with far fewer maria. After the end of Cold War, declassified documents revealed that Luna 3 had used unexposed film from a CIA reconnaissance balloon that had drifted over Soviet territory

The Zonds

In terms of Moon race after that, the USSR, generally, supported two separate programs. One program was based on using the Saturn-V class N1 Moon rocket to land a single cosmonaut on the Moon. The other, the L1 or Zond program, to send two cosmonauts on circumlunar missions without a Moon landing. The Zond essentially was a Soyuz spacecraft with the orbital module removed to save weight, replaced with a high-gain antenna and navigation instruments to enable lunar missions. The Zonds were precursors to planned crewed flights around the Moon. The Zond, originally, were a series beginning in 1964 of planetary probes intended to gather information about Venus, Mars, or the Moon. They mostly were failures are the Zond 3 only, by July 1965, turned the second spacecraft to photograph the far side of the Moon. The missions 4 through 8 were test flights belonging to the Russian response to the U.S. Moon race. A first batch of lunar Zond mission were failures also -- mostly at or after launch --, from March 1967 down to July 1968. Although it used the greater lift capability of the Proton rocket with a new upper stage to send the spacecraft and two cosmonauts on a free-return circumlunar trajectory, that capability was not enough to place the Zond into lunar orbit. After several failed launch attempts, the Soviets achieved partial success with Zond 4 in March 1968, testing spacecraft systems to lunar distances but not around the Moon. Due to problems with its navigation systems, Zond 4 did not accomplish a soft landing in Soviet territory as planned. After a few months of analyzing the problems with Zond 4, the Soviets were ready to try again

The Zond 5 launched successfully on September 15, 1968, from the Baykonur Cosmodrome in Kazakhstan, and after a short time in a low Earth parking orbit, the Proton’s upper stage ignited for a second time to send the spacecraft toward the Moon. The spacecraft carried a biological payload of wine flies, worms, plants and two Russian steppe tortoises. After a 3-day journey, Zond 5 passed 1,200 miles above the Moon’s farside and began its trip back toward Earth. At a distance of about 56,000 miles, the spacecraft took photographs of Earth. On September 21, Zond 5 reentered the Earth’s atmosphere but due to a guidance system error could not complete a soft landing in Soviet territory, splashing down in the Indian Ocean instead. Despite the landing problem, Zond 5 did complete the first successful circumlunar mission, safely returning its biological payload to Earth. U.S. Navy vessels photographed the spacecraft bobbing in the water as Soviet sailors on the Vasily Golovnin recovered it for return to Moscow via Bombay (now Mumbai), India and a Antonov-12 cargo transport aircraft. Technicians in Moscow removed the biological payload. Scientists found that the tortoises, the first living organisms to have made a circumlunar flight, had lost a little weight but were otherwise in good health. The flight of Zond-5 caused concern in the U.S. that the Soviets would place cosmonauts aboard the next Zond and complete the first crewed circumlunar mission. At about this time, a U.S. Corona reconnaissance satellite photographed an N-1 rocket on its pad at Baykonur. It is likely that top NASA managers like Administrator James E. Webb had access to this intelligence. The apparently successful Zond 5 mission coupled with the photos of the Soviet lunar booster on the launch pad may have contributed to the decision to send Apollo 8 on its circumlunar mission in December 1968, bringing the Moon landing one step closer

Zond 6 then launched successfully on Nov. 10, 1968, from the Baikonur Cosmodrome in Kazakhstan, and after a short time in a low Earth parking orbit, the Proton rocket’s upper stage ignited for a second time to send the spacecraft toward the Moon. The spacecraft carried a biological payload, probably similar to the one aboard its predecessor Zond 5. After a three-day journey that included a mid-course correction to refine its trajectory, Zond 6 passed 1,500 miles (2,420 kilometers) above the Moon’s far side. The spacecraft took photographs of both the Earth and the Moon’s near and far sides during the fly around. As it neared the Earth, however, trouble began when the capsule developed a leak from a faulty hatch seal and began to lose atmospheric pressure. The partial depressurization caused the loss of the biological payload. For its return to Earth on Nov. 17, Zond 6 used a novel skip reentry technique. After performing a initial entry into the Earth’s atmosphere, the spacecraft used aerodynamic lift to skip back into space before making a final entry. This technique allowed for a soft landing in Soviet territory without imparting excessive g-loads on the spacecraft and any crew that would have been on board. However, with the continuing loss of pressure inside the reentry capsule, a buildup of static electricity created a coronal discharge that triggered the spacecraft’s soft landing rockets and cut the parachute lines while it was still descending through 5,300 meters altitude. Although the capsule hit the ground at a high velocity, rescue forces were able to recover the film containers. The Soviets at the time did not reveal either the depressurization or the crash but claimed the flight was a successful circumlunar mission. Other Zond probes followed the Zond 5 until in October 1970 as only the Zond 6, 7 and 8 sucessfull while others failed mostly at or after launch also. Although with Apollo 11 the United States had won the race to the put the first man on the Moon, the Soviet Union had not entirely given up its lunar efforts. On Aug. 8, 1969 they launched the unpiloted Zond 7 on a circumlunar mission. On Aug. 11, Zond 7 looped around the far side of the Moon at a distance of 1,235 miles, returning spectacular photographs of the Moon and of an Earthrise. On Aug. 14, the spacecraft executed a skip-reentry maneuver and guided itself to a soft-landing near the city of Kustanai, in Kazakhstan (then part of the USSR). Zond 7 completed the first truly successful flight of the program. After one more flight in 1970, the program was cancelled

A unpiloted orbital lunar mission failed on July 3 as the N-1 Moon rocket exploded shortly after launch. That accident followed a first launch failure in February 1969, and set the N-1 program back by about two years. Undeterred by the N-1 explosion, the Soviets made one more attempt to upstage the Apollo 11 mission the USA were then to launch and which was to see the first man walk on Moon. They launched their Luna 15 -- a robotic lunar sample return mission -- on July 13 on a Proton rocket (after a failure in June). Four days later, as Apollo 11 was headed toward the Moon, Luna 15 entered an elliptical lunar orbit. Concerns at NASA that Luna 15 would interfere with the Apollo 11 mission were allayed as Academician Keldysh provided Luna 15's planned trajectory to NASA, the first such exchange in Soviet-American space relations. Initially planned for a July 20 landing, Soviet controllers concerned about the ruggedness of the planned landing site in the Mare Crisium kept Luna 15 in orbit an extra day. Finally, on July 21 after 52 orbits around the Moon, Luna 15 began its descent toward the surface as Armstrong and Aldrin had already completed their walk on the Moon and were preparing to lift off. Transmissions with Luna 15 ceased early however, and it is estimated that it crashed at excessive speed and its attitude off by several degrees. It was not before September 1970 that the Soviets managed a automatic lander at Moon, with the Luna 16 returning lunar soil samples from the Mare Fecunditatis