Category Soviet and Russian Lunar Exploration

By this time, the United States had launched their first satellite (Explorer 1, January 1958) and had made rapid progress in preparing a lunar programme. Korolev followed closely the early preparations by the United States to launch their first moon probe, called Pioneer. Learning that Pioneer was set for take-off on 17th August 1958, Korolev managed to get his first lunar bound R-7, with its brand-new Kosberg upper stage, out to the pad the same day, fitted with a Ye-1 probe to hit the lunar surface. The closeness of these events set a pattern that was to thread in and out of the moon programmes of the two space superpowers for the next eleven years.

There had been a lot of delays in getting the rocket ready and Korolev only managed to get this far by working around the clock. The lunar trajectory mapped out by Korolev and Tikhonravov was shorter than Pioneer. Korolev waited to see if Pioneer was successfully launched. If it was, then Korolev would launch and could still beat the Americans to the moon. Fortunately for Korolev, though not for the Americans, Pioneer exploded at 77 sec and a relieved Korolev was able to bring his rocket back to the shed for more careful testing.

A month later, all was eventually ready. The first Soviet moon probe lifted off from Baikonour on 23rd September 1958. Korolev may have worried most about whether the upper stage would work or not, but the main rocket never got that far, for vibration in the BVGD boosters caused it to explode after 93 sec. Despite launching three Sputniks into orbit, the R-7 was still taking some time to tame. Challenged about

repeated failures and asked for a guarantee they would not happen again, Korolev lost his temper and yelled: Do you think only American rockets explode?

The August drama came around a second time the following month. At Cape Canaveral, the Americans counted down for a new Pioneer, with the launch set for 11th October. In complete contrast to the developments at Cape Canaveral, which were carried out amidst excited media publicity, not a word of what was going on in Baikonour reached the outside world. Again, Korolev planned to launch the Ye-1 spaceship on a faster, quicker trajectory after Pioneer. News of the Pioneer launching was relayed immediately to Baikonour, Korolev passing it on in turn over the loudspeaker.

Not long afterwards, the news came through that the Pioneer’s third stage had failed. Korolev and his engineers now had the opportunity to eclipse the Americans. On 12th October, his second launching took place. It did only marginally better than the previous month’s launch, but the vibration problem recurred, blowing the rocket apart after 104 sec. Although Pioneer 1 was launched thirteen hours before the Soviet moon probe was due to go, the Russian ship had a shorter flight time and would have overtaken Pioneer at the very end. Korolev’s probe would have reached the moon a mere six hours ahead of Pioneer. According to Swedish space scientist and tracker Sven Grahn who calculated the trajectories many years later, ‘the moon race never got much hotter!’.

These two failures left Korolev and his team downcast. Although the R-7 had given trouble before, two failures in a row should not be expected, even at this stage of its development. Boris Petrov of the Soviet Academy of Sciences was appointed to head up a committee of inquiry while the debris from the two failures was collected and carefully sifted for clues. What they found surprised them. It turned out that the Kosberg’s new upper stage, even though it had never fired, was indirectly to blame. The new stage, small though it might be, had created vibrations in the lower stage of the rocket at a frequency that had caused them to break up. This was the first, but far from the last, time that modification to the upper stages of rockets led to unexpected consequences.

Devices were fitted to dampen out the vibration. Although they indeed fixed this problem, the programme was then hit by another one. It took two months, working around the clock, to get a third rocket and spacecraft ready. The third rocket took off for the moon on 4th December. As it flew through the hazardous 90-100 sec stage, hopes began to rise. They did not last, for at 245 sec, the thrust fell to 70% on the core stage (block A) and then cut out altogether. The rocket broke up and the remnants crashed downrange. The crash was due to the failure of a hydrogen peroxide pump gearbox, in turn due to the breaking of a hermetic seal which exposed the pump to a vacuum. It must have been little consolation to Korolev that the next American attempt, on 6th January, was also a failure, though it reached a much higher altitude, 102,000 km.

The Soviet failures were unknown except to those directly involved and the political leadership. America had experienced its own share of problems, but there the mood was upbeat. The probes had a morale-boosting effect on American public opinion. There was huge press coverage. The Cape Canaveral range (all it had been to date was an air force and coastguard station) became part of the American conscious­ness. Boosters, rockets, countdowns, the moon, missions, these words all entered the vocabulary. America was fighting back, and if the missions failed, there were credits for trying.

On the Russian side, there was little public indication that a moon programme was even under way. In one of the few, on 21st July 1957, Y. S. Khlebstsevich wrote a speculative piece outlining how, sometime in the next five to ten tears, the Soviet Union would send a mobile caterpillar laboratory or tankette to rove the lunar surface and help choose the best place for a manned landing [2]. Information about the Soviet space programme, which had been relatively open about its intentions in the mid-1950s, now became ever more tightly regulated. Chief ideologist Mikhail Suslov laid down the rubric that there could not be failures in the Soviet space programme. Only successful launchings and successful mission outcomes would be announced, he decreed, despite the protests at the time and later of Mstislav Keldysh. A cloud of secrecy and anonymity descended. The names of Glushko and Korolev now disappeared from the record, although they were allowed to write for the press under pseudonyms. Sergei Korolev became ‘Professor Sergeev’. Valentin Petrovich Glushko’s nom deplume was only slightly less transparent: ‘Professor G. V. Petrovich’, for it used both his initials (in reverse) and his patronymic.

So whenever spaceflights went wrong, their missions were redefined to prove that they had, indeed, achieved all the tasks set for them. This was to lead Soviet news management, in the course of lunar exploration, into a series of contradictions, blunders, disinformation, misinformation and confusion. But it was best, as in the case of the first three moonshots, that nothing be known about them at all.

The lunar lander was called the Ye-6. In the event, there were two variants: the Ye-6, used up to the end of 1965; and the Ye-6M, used in 1966. The Ye-6 series had two modules. The main and largest part, the instrument compartment, was cylinder­shaped, carried a combined manoeuvring engine and retrorocket, orientation devices, transmitters and fuel. The lander, attached in a sphere on the top, was quite small, only 100 kg. It was ball-shaped and once it settled on the moon’s surface, a camera would peep up to take pictures. It followed very closely the popular image of what an alien probe landing on Earth would look like.

The main spacecraft was designed to carry the probe out to the moon and land it intact on the surface. The engine, built by Alexei Isayev’s OKB-2, would be fired twice: first, for a mid-course correction, with a maximum thrust of 130 m/sec; and, second, to brake the final stage of the descent. The engine was called the KTDU-5, an abbrevia­tion from Korrektiruiushaya Tormoznaya Dvigatelnaya Ustanovka, or course correc­tion and braking engine) and it ran off amine as fuel and nitric acid as oxidizer. The next most important element was the I-100 control system, built by Nikolai Pilyugin’s Scientific Research Institute NII-885. This had to orientate the spacecraft properly for the mid-course correction and the landing. The mid-course correction was intended to provide an accuracy of 150 km in the landing site. The main module relied on batteries rather than solar power.

The final approach to landing would be the most difficult phase. The rocket on the 1,500 kg vehicle had to fire at the correct angle about 46 sec before the predicted landing. It must brake the speed of the spacecraft from 2,630 m/sec 75 km above the moon to close to 0 during this period. Too early and it would run out of fuel before reaching the surface, pick up speed again and crash to pieces. Too late and it would impact too fast. The main engine was designed to cut out at a height of 250 m. At this stage, four thrusters were expected to slow the spacecraft down to 4 m above the

surface. A boom on the spacecraft would then detect the surface. As it did so, gas jets would fill two airbags and the lander would be ejected free to land safely. Four minutes after landing, a timer would deflate the bags and the lander would open from its shell.

Landing cabin

with petals with arms

Weight

Ye-6 instruments

• Ye-6M (Luna 13).

• Camera.

• Radiometer.

• Dynamograph/penetrometer (‘gruntmeter’).

• Thermometer.

• Cosmic ray detector.

The lander was egg-shaped, pressurized, metallic-looking and made of aluminium. Inside were a thermal regulation system, chemical batteries designed to last four days, transmitters and scientific equipment. Once stable on the surface, four protective petals would open on the top to release the four 75 cm transmitting aerials. The most important element was of course the camera. Although often described as a television camera, it was more accurately called a pinpoint photometer and took the form of a cylinder with a space for the scanning mirror to look out the side. These are optical mechanical cameras and do not use film in the normal sense, instead scanning for light levels, returning the different levels by signal to Earth in a video, analogue or digital manner. The system was designed by I. A. Rosselevich, built by Leningrad’s Scientific Research Institute NII-380 and was based on systems originally used on high-altitude rockets. The camera was small, only 3.6 kg in weight and used a system of mirrors to scan the lunar surface vertically and horizontally over the period of an hour working on only 15 watts of electricity. The lander would transmit for a total of five hours over the succeeding four days, either on pre-programmed command or on radioed instruc­tions from the ground.

A safe landing required as vertical a descent as possible. From the photography point of view, the Russians wanted to land a spacecraft during local early dawn. The lunar shadows would therefore be as long as possible, providing maximum contrast and enabling scale to be calculated. Once again, Keldysh’s Mathematics Institute calculated the trajectories. Earth-moon mechanics and lighting conditions were such that a direct early dawn descent could come down in only one part of the moon, the Ocean of Storms. This is the largest sea on the moon, covering much of its western hemisphere.

The Americans built a comparable spacecraft, Ranger. Here, the Americans intended to achieve the double objective of photographing the lunar surface and achieve a soft-landing. On Ranger, the main spacecraft was a hexagonal frame which contained the equipment, engine and cameras. As Ranger came down toward the
lunar surface, photographs would be taken until the moment of impact. Ranger’s soft – landing capsule would use a different landing technique: 8 sec before impact and at an altitude of 21.4 km, the landing capsule, with a retrorocket, would separate from the crashing mother craft. The powerful solid rocket motor would cut its speed. The cabin would separate, impact at a speed of not more than 200 km/hr and then bounce onto the lunar surface. Ranger’s landing capsule was about half the size and weight of the Ye-6. It was made out of balsa wood and the instruments would be protected by oil. There was a transmitter and only one instrument: a seismometer (no camera).

Undeterred though undoubtedly disappointed, Korolev hoped to be fourth time lucky. He aimed to make his fourth attempt for New Year’s Day. Preparing the rocket in such record times was extremely difficult and the engineers complained of exhaustion. Baikonour was now in the depths of winter and temperatures had fallen to —30°C. There were two days of delays and the probe was not launched until the evening of 2nd January 1959.

Blocks B, V, G and D fell away at the appropriate moment. The core stage, the block A, cruised on. The time came for block A to fall away. Now, Semyon Kosberg’s 1,472 kg small upper stage faced its crucial test. With apparently effortless ease, the stage achieved escape velocity (40,234 km/hour) and headed straight moonwards. The final payload, including the canister, sent moonbound weighed 361 kg, but the actual moon probe was 156 kg. The spacecraft was spherical and although the same shape as the first Sputnik was four times heavier, with a diameter of 80 cm, compared with the 56 cm of Sputnik. It was pressurized and the four antennae and scientific instruments popped out of the top. Signals would be sent back to Earth on 183.6 MHz for trajectory data and 19.993 MHz for scientific instruments (this is called ‘downlink’) and commands sent up on 115 Hz (‘uplink’). The radio system had been designed and built by Mikhail Ryanzansky of the NII-885 bureau, one of the original Council of Designers. To save battery, signals would be sent back for several minutes or longer at a time at pre-timed intervals, but not continuously. The upper stage also had a transmitter which sent back signals in short bursts every 10 sec for several hours as it headed into deep space.

The spacecraft carried instruments for measuring radiation, magnetic fields and meteorites. The magnetometer was only the second carried by a Soviet spaceship and

arose from a 1956 meeting between chief designer Sergei Korolev and the first head of the space Magnetic Research Laboratory, Shmaia Dolginov (1917-2001) [3]. He headed the laboratory in the Institute of Terrestrial Magnetism (IZMIRAN) where he had mapped the Earth’s magnetic field by sailing around the world in wooden ships using no metallic, magnetic parts. He worked with Korolev to install a magnetometer on Sputnik 3, which duly mapped parts of the Earth’s magnetic field. Now they would be installed on lunar probes to detect magnetic fields around the moon. The magnet­ometer was called a triaxial fluxgate magnetometer with three sub-instruments and sensors with a range of —3,000 to 3,000 gammas.

Similarly, ion traps first flown on Sputnik 3 would be used on the lunar probe. Ion traps were used to detect and measure solar wind and solar plasma and were developed by Konstantin Gringauz (1918-1993), who had been flying his traps on sounding rockets as far back as the 1940s. He had famously built the transmitter on Sputnik and was the last man to hold it before it was put in its carrier rocket. The meteoroid detector was developed by Tatiana Nazarova of the Vernadsky Institute. Essentially, it comprised a metal plate on springs which recorded any impact, however tiny. The cosmic ray detector was developed by Sergei Vernov (1910-1982) of the Institute of Nuclear Physics in Moscow, who had been flying cosmic ray detectors on balloons since the 1930s.

Instruments on the First, Second Cosmic Ship

Gas component detector.

Magnetometer (fields of Earth and moon). Meteoroid detector.

Cosmic ray detector.

Ion trap.

1 kg of sodium vapour.

As the probe moved rapidly between 20,000 km and 30,000 km out from Earth, it was possible to use the radio signals to make very precise measurements of its direction and velocity. From these, it was apparent that the spacecraft would not hit the moon after all, though unlike the American spacecraft it would not fall back to Earth. On 3rd January, when 113,000 km out from Earth, the spacecraft released a golden-orange cloud of sodium gas so that astronomers could track it. The cloud was visible in the sky over the Indian Ocean and it confirmed that the probe would come quite close to the moon.

One problem was: what to call it? In Moscow, it was referred to as ‘The First Cosmic Ship’ because it was the first spacecraft to leave the Earth’s gravitational sphere of influence at escape velocity. The Russians appeared reluctant to name it a moon probe, because that would imply that it was supposed to impact on the moon, which of course it was. Already, the Suslov decision was having its baleful impact. On 6th January, Anatoli Blagonravov of the Academy of Sciences denied flatly that it was ever intended to hit the moon but to pass close by instead [4]. Later, in 1963, it was retrospectively given the name of Luna 1. In the West, the first three probes were called Lunik, but this was a media-contrived abbreviation of ‘Luna’ and ‘Sputnik’ and was never used by the Russians themselves. Several of the early designators for the Soviet space programme were unclear and applied inconsistently, but thankfully never as confusingly so as the early Chinese space programme.

On 4th January, the First Cosmic Ship passed by the moon at a distance of 5,965 km some 34 hours after leaving the ground. It went on into orbit around the Sun between the Earth and Mars between 146.4 million kilometres and 197.2 million kilometres. The probe was a dramatic start to moon exploration: it ventured into areas of space never visited before. Signals were picked up for 62 hours, after which the battery presumably gave out, at which point the probe was 600,000 km away.

The first round of results was published by scientists Sergei Vernov and Alexander Chudakov in Pravda on 6th March 1959. More details were given by the president of the Academy of Sciences, Alexander Nesmyanov, opening the Academy’s annual general meeting that spring, which ran from 26th to 28th March. First, no magnetic field was detected near the moon, but scientists were aware that it was possibly too far out to detect one. The magnetometer noted fluctuations in the Earth’s magnetic field as the First Cosmic Ship accelerated away. A contour map of the Earth’s radiation belts was published, showing them peak at 24,000 km and then fall away to a low level some 50,000 km out. Second, the meteoroid detector, which was calibrated to detect dust of a billionth of a gramme, suggested that the chances of being hit by dust on the way out to the moon or back was minimal. Third, in a big finding, Konstantin

Gringauz’s ion traps detected how the Sun emitted strong flows of ionized plasma. This flow of particles was weak, about 2 particles/cm2/sec, because the sun was at the low point in its cycle, but the ship’s ion traps had determined the existence of a ‘solar wind’. This was one of the discoveries of the space age and Gringauz estimated that the wind blew at 400 km/sec [5].

A tracking station had already been built for the moon probes of 1958-60, located in the Crimea. Its southerly location was best for following a rising moon. The Crimea around Yevpatoria offered several advantages for a tracking system. Originally, the tsars had built their summer homes around there and it had now become a resort area, meaning that it was well served by airfields. There were defence facilities in the region and military forces who could assist in construction.

The tracking system was considerably expanded in 1960. This was done to serve the upcoming programme for interplanetary exploration, but these new facilities could also be used for lunar tracking. The new construction at the Yevpatoria site was called the TsDUC, or Centre for Long Range Space Communications. The TsDUC actually comprised two stations with two receivers (downlink) and one transmitter (uplink), facilitated by a microwave station, which transmitted data from the receiver stations to another microwave system in nearby Simferopol and thence on to other locations in the USSR. The records are confusing about what was actually built at the time and where and little was said about them publicly, presumably to hide Soviet tracking capabilities from the snooping Americans. We know that the Amer­icans had good intelligence maps of the Yevpatoria system from 1962, but it would be surprising if they had not had good details a little earlier.

For the moment, two sets of eight individual duralium receiving dishes of 15.8 m were built on a movable structure, designed to tilt and turn in unison. Two were built 600 m apart at what the Americans called ‘North Station’ and a set of half the size, 8 m transmitting dishes called Pluton at what they called ‘South Station’. North Station was the largest complex of the two, surrounded by 27 support buildings, 15 km west of Yevpatoria. To construct the receiving stations, Korolev was forced to improvise. He came up with the idea of using old naval parts for the station: a revolving turret from an old battleship, a railway bridge for support and the hull of a scrapped submarine. They received signals on the following frequencies: 183.6, 922.763, 928.429 MHz and 3.7 GHz.

South Station was to the southeast and much closer to Yevpatoria, 9 km. It comprised one, later eight 8 m dishes in a similar configuration to, but half the size of the duo at North Station. Transmission power was rated at 120 kW and its range was estimated at 300 million km. Transmissions were sent at 768.6 MHz.

Even though chief designer Yevgeni Gubensko died in the middle of construction, Yevpatoria station went on line on 26th September I960, just in time for the first, but unlucky Mars probes. The facilities there were originally quite primitive, ground controllers being provided with classroom-style desks, surrounded by walls of com­puter equipment. Modern wall displays did not come in until the mid-1970s. Still, it was the most powerful deep space communications system until NASA’s Goldstone Dish came on line in 1966. In 1963, just in time for the new Ye-6 missions, the lunar programme acquired a dedicated station, a 32 m dish in Simferopol called the TNA-400.

Until a mission control was opened in Moscow in 1974, Yevpatoria remained the main control for all Russian spaceflights, not just the interplanetary ones. It was normal for the designers to fly from Baikonour Cosmodrome straight to Yevpatoria to oversee missions. The Americans, by contrast, had a worldwide network oftracking stations, with large dishes in California, South Africa and Australia. Dependence on one station at Yevpatoria imposed two important limitations on Soviet lunar probes. First, the arrival of a spacecraft at the moon had to be scheduled for a time of day when the moon was over the horizon and visible in Yevpatoria, so schedules had to be calculated with some care in advance. Second, as noted during the 1959 missions, there was no point in having Soviet moon probes transmit continuously, for their signals could not be picked up whenever the moon was out of view. Instead, there would be short periods of concentrated transmission, called ‘communications sessions’ sched­uled in advance for periods when the probes would be in line of sight with Yevpatoria. This required the use of timers and sophisticated systems of control, orientation and signalling.

Korolev and his colleagues attempted to get around the limits imposed by the Yevpatoria station. If they lacked friends and allies abroad to locate tracking dishes, there were always the oceans. Here, three merchant ships were converted to provide tracking for the first Mars and Venus missions, but they could also serve the moon programme. These ships were the Illchevsk, Krasnodar and Dolinsk and their main role was to track the all-important blast out of parking orbit, which was expected to take place over the South Atlantic. The ships were a helpful addition, but they had limitations in turn. First, ships could not carry dishes as large as the land-based dishes; and, second, they were liable to be disrupted in the event of bad weather at sea, which made it difficult to keep a lock on a spacecraft in a rolling sea.

The First Cosmic Ship was denounced in some quarters of the Western world as a fraud and one writer, Lloyd Malan, even wrote a book about it called The big red lie.

The reason? Few people in the West picked up its signals, even though the Russians had, as usual, announced their transmission frequencies (183.6, 19.993 and 19.997 MHz). Not only that, but the original Tass communique announcing the mission had told observers when the moonship would be over Hawaii, when the sodium cloud would be released and even where to look for it (the constellation Virgo).

The explanations were mundane, rather than conspiratorial. The Russians had inconveniently launched the First Cosmic Ship late on a Friday night and most professional observers had long since gone home for the weekend. By the time the Earth had rotated in line of sight for American observatories, the First Cosmic Ship was already well on its way and ever more difficult to pick up. In the event, signals were received on the next day by Stanford University in California when it was about 171,000 km out. At the Jet Propulsion Laboratory in California, staff were recalled over the weekend in a frantic effort to locate the spacecraft, which they eventually did when it was 450,000 km out, eight hours after it passed the moon. American military signal stations probably also tracked the spacecraft in Hawaii, Singapore, Massachusetts and Cape Canaveral, but if they received signals, they never told.

In Britain, the director of the large radio telescope at Jodrell Bank, Bernard Lovell, was at home listening to Johann Sebastian Bach’s Fantasy and fuge. Jodrell Bank had been established by a physics professor, Bernard Lovell, who had spent the war developing radar to detect enemy planes and ships. In peacetime, he now adapted ex-army radars to study cosmic rays and meteor trails. This work was so promising that in 1950 he got the go-ahead for a large radio telescope for radio mapping of deep space objects and this was, fortuitously, completed just in time for the launching of Sputnik seven years later. There was some debate in Jodrell Bank as to whether the huge dish telescope should be used to track spacecraft at all, but the station had considerable financial liabilities and the glow of world media publicity attached to the station’s role in tracking spacecraft soon enabled that debt to be cleared. In fact, it was not the Russians but the Americans who first brought Jodrell Bank into the moon programme, paying for the use of its facilities in 1958 for the early American moon probes. Jodrell Bank had tried but failed to pick up the First Cosmic Ship, but, Bernard Lovell added, the station still believed that the probe existed! He put down his failure to obtain signals as due to inexperience. He had imagined that it would transmit continuously and had not understood the Russian system of periodic transmission, the ‘communications session’ [6].

The early moon shots of the United States and the Soviet Union had much in common. The first and the most obvious was their high failure rate. With the successful launching of the First Cosmic Ship, Russia and America had each tried four times. One Russian probe had reached but missed the moon. One American probe had reached 113,000 km, the other 102,000 km before falling back. All the rest had exploded early on.

Here, the similarities ended. The Russian Ye-1 probe was large, weighing 156 kg, with a simple (albeit elusive) objective: to impact on the moon. Six instruments were carried. By contrast, the American Pioneer probes were tiny, between 6 kg and 39 kg. They carried similar instruments: for example, like the early Russian probes, Pioneer 1 carried a magnetometer. The early American missions were more ambitious, aiming for lunar orbit and to take pictures of the surface of the moon. The camera system on Pioneer was tiny, weighing only 400 g, comprising a mirror and an infrared thermal radiation imaging device.

The First Cosmic Ship was hailed as a great triumph in the Soviet Union. The third year of space exploration could not have opened more brightly. Stamps were issued showing the rocket and its ball-shaped cargo curving away into a distant cosmos.

Throughout 1962, the Ye-6 was put through a rigorous series of ground tests. These focused on the landing sequences, the operation of the airbags and ensuring their subsequent successful deployment.

The first Ye-6 was successfully launched into Earth parking orbit on 4th January 1963, four years and two days after the First Cosmic Ship. Block L was due to fire from its parking orbit over the Gulf of Guinea toward the end of the first orbit to send the new spaceship moonbound. The Dolinsk was steaming below to track the signals.

Once again, the block L let everyone down. The power system in the 1-100 control unit appears to have failed, for the electrical command to ignite block L was never sent. The moon probe orbited the Earth for a day before breaking into fragments and burning up. A second attempt was made a month later, on 3rd February. Control of the pitch angle began to fail at 105.5 sec. 1-100 control was lost just as block I was due to fire. There was no third-stage ignition and the two upper stages crashed into the Pacific near Midway Island. Both launches were detected by the Americans, who had no difficulty in assessing them as failed moon probes.

Sorting out the I-100 control unit took two months. The next probe was launched on 2nd April 1963 and became the first Russian moon probe to leave a parking orbit for the moon. It was named Luna 4 (no more ‘cosmic ships’ or ‘interplanetary stations’), although in reality it was the twelfth Russian moonshot. Its precise purpose was not revealed, except to say that it would travel to ‘the vicinity of the moon’. Although the Russians did not specifically ask Jodrell Bank to track Luna 4, they issued transmission frequencies (183.6 MHz) and gave navigational data, an indirect invitation to do so. Jodrell Bank picked up signals for six hours, two days after the probe left Earth. The Russian receiving stations followed the mission from their new base in the Crimea and the spacecraft was also picked up visually as a 14th magnitude star. The Soviet news agency, Tass, was upbeat:

Scientists have to clarify the physical conditions cosmonauts will meet, how they are to overcome landing difficulties and how they should prepare for a prolonged stay on the moon. The human epoch in the moon’s history is beginning. There will be laboratories, sanatoria and observatories on the moon.

This heady enthusiasm soon evaporated. The following day, it became clear that the astro-navigation system had failed and that it would be impossible to perform a mid­course manoeuvre. The next day, on 4th April, the USSR reluctantly announced that Luna 4 would fly ‘close to’ the moon at 9,301 km the following day (in reality, it may have come slightly closer, 8,451km). Jodrell Bank listened in carefully for 44min during the point of closest passage. Contact was lost two days later and Luna 4 ended up in a highly eccentric equatorial Earth orbit of 89,250 by 694,000 km, taking 29 days per revolution and may have been eventually perturbed out of it into solar orbit. The Russians claimed – quite unconvincingly – that a lunar flyby was all that had been intended. But they shut up about health resorts on the moon for the time being.

The three failures in four months forced a review of the programme, this time headed up by Mstislav Keldysh, who was now president of the Academy of Sciences. The investigators never determined the true cause of the failure of Luna 4. All that was known for certain was that the mid-course correction had never taken place because the astro-navigation system had failed, which meant that the spacecraft could not be orientated for the burn in the first place. The Keldysh investigation did find many problems with the system itself and these were corrected over the following year. There was abundant evidence of the programme being prepared in too much of a hurry and quality control suffering as a result.

It was another year before the next Ye-6 was made ready for launch. The background was not propitious, for two more 8K78 Molniya rockets with test probes for Venus had failed in the past six months. What should have been Luna 5 was launched on 21st March 1964, but a rod broke in the block I stage, a valve failed to open fully, it never reached full thrust, cut off at 489 sec and the stage crashed back to Earth. On the 20th April 1964, a month later, the next Ye-6 suffered the same fate, but this time the connecting circuitry between the BOZ and the I-100 failed, the mission ending after 340 sec. Despite further efforts to resolve the problems in the upper stage, the next moon rocket was lost as well on 12th March 1965. This time, block L failed to ignite due to a transformer failure. The mission was given the designator of Cosmos 60, but the ever-watchful Americans knew at once that it was a moon failure. Confirmation that this was the case came when, many years later, it became known that Cosmos 60 had carried a gamma ray detector of the type later flown on Luna 10 and 12. Even though the mission failed as a moon probe, useful scientific results on cosmic rays were obtained [1].

This time, more significant steps were taken to address the problems ofintegrating block 1, block L, the BOZ and the I-100. The whole system was re-worked and re­wired, with separate control systems installed on both block L and the Ye-6. Little good did it do, for the next Luna crashed to destruction on 10th April 1965. This time the pressurization system for the liquid oxygen tank of block I failed, causing the spacecraft to crash into the Pacific. The new guidance system was never tested. This was the fourth failure in a row since Luna 4. Indeed, since the Automatic Inter­planetary Station, Russia had attempted to launch nine probes to the moon, none had been successful and only one had been announced. The level of failures represented a rate of attrition no programme could sustain and questions were being asked in the Kremlin by now.