Category Soviet Robots in the Solar System

INTRODUCTION

Any great enterprise is the product of people. It is people who make things happen. Institutions are the means by which great enterprises are realized, but it is the people in these institutions, and in particular the leaders of these institutions, that drive the mechanisms to create great products. And so it is in the space exploration enterprise. We begin the story of the Soviet Union’s space exploration program in the 20th Century with a description of the people who led the development of this great enterprise. While there were many administrators, engineers and scientists who were essential, we have room here only to describe those at the top of the enterprise, those whose personal and institutional power created the USSR’s space program. At the top are the Communist Party leaders and government ministers who had control over selecting and funding national projects; second, and most particularly, the individual Chief Designers of the space program who proposed the projects; third the directors of the design bureaus which were responsible for building rockets and spacecraft for the projects; and finally the President of the Soviet Academy of Sciences, who besides his own leadership of the space program provided academic resources via the directors of the Academy’s research institutes where space mission goals were developed using the rockets and spacecraft built by the design bureaus.

The single most important individual in the development of the Soviet space program after WW-II was Sergey Pavlovich Korolev. After. Toseph Stalin decided to make rocket development a national priority at the end of the war, Korolev was retrieved from exile in a labor camp, together with others from his small band of engineers that built research rockets before the war. They started with the V-2 and a group of captured German engineers, just as occurred in the US. During the 1940s and 1950s Korolev’s design bureau developed the USSR’s first long range rockets using the German rocket engineers’ expertise to build their own design skills. By the mid-1950s the German engineers had been generally dismissed, and the enterprise was entirely Russian. Korolev began testing his R-7 ICBM in the spring of 1957, the rocket that would launch not only Sputnik and other early Earth satellites, but

W. T. Huntress and M. Y. Marov, Soviet Robots in the Solar System: Mission Technologies 5

and Discoveries, Springer Praxis Books 1, DOl 10.1007/978-1-4419-7898-1_2,

© Springer Science+Business Media, LLC 2011

almost all of the Soviet lunar and planetary missions throughout the 1960s and all Soviet cosmonauts, in upgraded and modified versions, this venerable rocket has become the core of the Soyuz launcher that is used commercially today for both manned and unmanned missions.

Korolev was an excellent engineer and designer, with considerable leadership and political skills. These qualities and his mission successes made him the darling of the Soviet space program. His identity was kept secret and he became known as ‘Chief Designer’, a term invented for the titular head of the Soviet space program. There were only two others that followed him after his death in 1966, but neither man had the full measure of qualities possessed by Korolev and the program seemed to lose much of its driving force. Had Korolev remained in charge, the USSR may have landed a cosmonaut on the Moon – even if later than planned and after the Americans. The Chief Designer of the Soviet space program, the de-facto leader inside Kremlin circles, was at the same time a director of one of the implementing design bureaus. There was no equivalent in the US: Wernher von Braun had a similar leadership role but was not at the same time the Administrator of NASA. In the USSR, there was no equivalent of NASA. The space enterprise was only a portion of the government’s Ministry of General Machine Building, which had wide control over all of Soviet space industry and the design bureaus that implemented the policies of the ministry.

The design bureaus and research institutes were the places where all the hardware

was developed and built to execute the Soviet space program, except for the science instruments supplied by the Soviet Academy of Seiences. The directors, also known as ‘Chief Designers’, of the several design bureaus and research institutes were the key ‘movers and shakers’ of the program. At the beginning of the Soviet rocket and space enterprise, Korolev established a Council of Chief Designers to coordinate all efforts in rocket development and space exploration. The members of the Council are shown in Figure 2.1. Council member Academician Valentin Petrovich Glushko (1908-1989) was an early colleague of Korolev’s before WW-II and supplied the rocket engines for the R-7, but later he became a dedicated rival to Korolev. He was one of the most important figures in the history of the Soviet program, and his role following Korolev’s death is described later in this chapter. Academician Nikolay Alexeevich Pilyugin (1908-1982) was Chief Designer of МІР and responsible for autonomous control systems (avionics) for rockets and spacecraft. Pilyugin was one of Korolev’s closest colleagues and pioneered the development of flight computers and precision avionics for autonomous navigation. Corresponding member Mikhail Sergeevich Ryazansky (1909 1987) was Director and Chief Designer of N11-885 and developed radio systems including on board transmitters, receivers, radio command links and terrestrial antennas for rockets and deep space missions. In particular, he pioneered the study of radio systems to facilitate autonomous navigation by vehicles in deep space and the development of imaging systems for spacecraft. Academician Alexey Fedorovich Bogomolov (1913 2009) w’as Director of Design Bureau OKB МЫ (until 1989) and principally responsible for the development of on board radio telemetry and trajectory tracking, in addition to terrestrial antennas for rockets and spacecraft. He also greatly contributed to radar remote-sensing techniques including the instrument Гог mapping of Venus by Venera 15 and 16. Academician Vladimir Pavlovich Barmin (1909 1993) was Chief Designer of all ground complexes for ballistic missiles and space launchers. He also contributed to the development of soil – sample devices for Luna and Venera missions. Academician Victor Ivanovich Kuznetsov (1913 1991) w as Chief Designer and Director of N11-10, and as such he developed gyroscopes for rockets and spacecraft and pioneered inertial navigation systems in the USSR.

The design bureaus were all in competition with one another. One or the other of the directors, such as Korolev, was by force of personality and political connection the LChief Designer’ of the whole space program. With no dedicated governmental space administration to marshal the competition between design bureaus, the Soviet space program was rife with rivalry, animosity and political intrigue. The resulting inefficiencies were wasteful of resources and a cause for much delay and many a failure. After Korolev died, there was no one with all the personal skills necessary to hold it all in check.

Almost equivalent in stature to Korolev was Mstislav Vsevolodovich Keldysh, head of the Institute of Applied Mathematics and after 1961 President of the Soviet Academy of Sciences. While Korolev w as the ‘Chief Designer’ of the Soviet space program, Keldysh was ‘Chief Theoretician’. They worked together both to advocate and implement the space exploration program. From 1956 until his death in 1978. Keldysh was the Chair of the highly recognized In ter-Departmental Scientific and

Technical Council on Space Research (MNTS KI; Mezhduvcdomstvennyi Nauchno-Tekhnicheskii Soviet po Kosmicheskim Issledovaniyam) which was responsible for space science and technology development in the Soviet Union. The Council and the Academy determined the objectives for the space program, advised the government and recommended individual projects, provided expertise in space navigation, and supplied scientific investigations for flight missions. Acting together, Korolev and Keldysh were responsible for many of the achievements of the space program.

The final highly influential group were the directors of research institutes of the Soviet Academy of Sciences. The two leading space science organizations were the Vernadsky Institute of Geochemistry and Analytical Chemistry established in 1947 and the Institute for Space Research set up in 1965. The Academy’s science institutes devised the science objectives and instruments for space missions. The leading design bureau and science institute directors were strong individuals who advised Korolev and Keldysh on which missions to fly and determined what science investigations would be carried.

.Minister 9

The UR-500 Proton launcher was initially developed as an ICBM to carry heavier warheads over longer ranges than the R-7. By 1961 Vladimir Chelomey’s OKB-52 had developed a practical storable propellant fast-response ICBM for the military and Korolev’s R-7 had become a space launcher, so Khrushchev naturally enlisted Chelomey to build the larger rocket to deliver the new H-bomb. Chelomey’s answer was the Universal Rocket 500, or UR-500. However, as with fission devices, the Soviets soon learned how to make much lighter thermonuclear devices and the UR – 500 was canceled by the military. Chelomey convinced the government that his rocket, augmented with an upper stage, eould send cosmonauts on direct flights to the Moon for circumlunar missions. At that time, Korolev was envisaging achieving this by two launches and an Earth orbital rendezvous. Chelomey’s scheme would be simpler. lie succeeded in wresting the circumlunar project from OKB-1 and kept the UR-500 program alive with support from Keldysh, who wisely recognized that such a booster would have many important applications. In 1965 Korolev succeeded in regaining the spacecraft and fourth stage combination for the circumlunar project, his reasoning being that Chelomey had never built a spacecraft and OKB-1 already had one in production. The mission would use Chelomey’s booster but with the fifth stage from Korolev’s N-l rocket serving as its fourth stage. For use on the Proton stack, the N-l s Block D guidance package was removed and this function had to be provided by the spacecraft.

The three stages of the UR-500 were all powered by engines that burned nitrogen tetroxide and IJDMH. a combination despised by Korolev. The first stage had six highly advanced and very efficient closed-cycle RD-253 engines made by Korolev’s nemesis. Valentin Glushko in OKB-456. The second and third stages were powered by engines built by Kosberg s OKB-154. A feature of the first stage s design is that the UDMH is contained in six tanks arranged around the larger central oxidizer tank. This unique design was imposed by width limitations of the railway system, which precluded vehicle widths greater than 4.1 meters. The various tanks were therefore delivered separately and assembled at the launch site. A specialised rail transporter then took the completed vehicle to the pad.

The UR-500 began Hying only four years after being commissioned, and showed immediate promise with a two-stage version on July 16, 1965. successfully placing into orbit a very heavy Proton satellite to study cosmic rays; hence its popular name. The fifth launch on March 10, 1967. was the first for the four-stage IJR-500K. also know n as the Proton-K. This had Korolev s restartable Block D upper stage, w hich used his preferred propellants of kerosene and LOX. The payload w as the first in the

series of tests of the lunar Soyuz, disguised hy the name Zond, and was considered a success. The power of the Proton-K was irresistible for lunar and planetary missions, and it replaced the Molniya for lunar and Mars missions in 1969 and Venus missions in 1975. It became the workhorse for lunar and planetary missions in the 1970s and continued into the 1990s. Being much more powerful than the Molniya it facilitated much heavier and more sophisticated lunar and planetary spacecraft. Its lift capacity made possible such missions as lunar rovers, lunar sample returns, and soft landing missions on Mars and Venus. It was used for Zond 4 to 8, Luna 15 to 24, Mars 2 to 7, Venera 9 to 16, Vega 1 and 2, Phobos 1 and 2, and Mars-96. Several versions of the Block D fourth stage were developed for the Proton-K. The original was used for Luna 15 to 23, Zond 4 to 8, Mars 2 to 7 and Venera 9 and 10; the D-l version was used for Luna 24, Venera 11 to 16 and Vega 1 and 2; and the D-2 was employed for Phobos 1 and 2 and Mars-96. In all these missions, the spacecraft was required to supply guidance for the Block D stage.

One of the glaring reasons for so many failures in Luna, Zond, Venera and Mars missions in the late 60s and early 70s wns poor performance of the Proton vehicle. Succeeding in its initial launch and in two of its next three launches in 1965-66, its initial performance appeared promising. But its record in the 3 years from March 1967 to February 1970 was abysmal. Ten of nineteen spacecraft were lost w’hen the Proton failed to deliver the Block D to Earth orbit. Another three achieved orbit but were stranded when the second burn of the Block D failed. Only six of the nineteen launches were fully successful. Sixteen were interplanetary, and the Proton failed in eleven cases – four failures out of eight Zond launches to the Moon, five failures out of six Luna launches, and the failure of both Mars launches in 1969. Unfortunately, the failures were distributed throughout the vehicle including all stages, so it was very difficult to make the vehicle reliable.

NPO-Lavochkin was so concerned at the Proton failures that General Designer Gcorgi Babakin met with the Minister of General Machine Building in March 1970 to demand action. *Aftcr the rocket underwent a full engineering review a number of improvements were made, and the vehicle was re-qualificd in a successful test flight in August 1970. After this, the success record improved dramatically and eventually the Proton became one of the most reliable workhorses in the Soviet launcher fleet. Indeed, it today enjoys an excellent reputation and a large share of the commercial launch market.

N-l MOON ROCKET

The N-l launcher was the Soviet counterpart to the Saturn V, and was developed for the same role. It had five stages, stood 105 meters tall, weighed 3,025 metric tons at launch and could place 95 metric tons in low Earth orbit. In contrast, the Saturn V

had four stages (treating the Apollo lunar module as equivalent to N-l’s fifth stage in the powered descent phase of the mission profile), stood 110 meters tall, weighed 3,0.19 metric tons at launch and could place 119 metric tons in low Earth orbit.

The first stage of the N-l had 30 NK-33 non-gimbaled 1.51 MN engines arranged in concentric rings with 24 around the outer ring and 6 around the inner. Large graphite vanes mounted on four of the outer ring engines provided thrust vectoring. If one of the engines malfunctioned, both it and the one diametrically opposite had to be shut down. The second stage had eight NK-43 1.76 MN engines, and the third stage had four NK-39 0.4 MN engines. The first three stages were to insert the fourth and fifth stages into low’ Earth orbit. At the appropriate time the fourth stage, powered by four NK-31 0.4 MN engines, would send the fifth stage, incorporating the orbiter/lander. towards the Moon. The LNK’ engines were made by OKB-276, headed by Nikolai Dmitriyevich Kuznetsov, and used a LOX-kerosene combination. The fifth stage was the Block D which Korolev adapted to serve as the fourth stage of the Proton-K. It was powered by a single Melnikov RD-58 engine that also used LOX-kerosene, and was to perform midcourse maneuvers, lunar orbit insertion and the majority of the powered descent, being discarded in the final phase to enable the lander to use its own engine to perform the soft landing.

The N-l failed test flights in February and July of 1969, in the latter case with a spectacular explosion at liftoff that dashed Soviet hopes of competing with the US Apollo program. The N-1 had another test flight in 1971 and a final test in 1972. The

first stage failed each time and the project was abandoned. Its Achilles’ heel was the large number of engines that all had to work without adversely affecting the others. Remarkably, there were no static test firings. The launch attempts in 1969 carried an automated form of the Soyuz 7K-LI drcumlnnar spacecraft and a dummy LK lunar lander. The launches in 1972 carried an automated Soyuz 7K-LOK lunar orbiter and dummy LK lunar lander. The only successful result was proof that the escape rocket could pull the crew module clear of the exploding rocket.

Campaign objectives:

Korolev’s second step after demonstrating the ability to hit the Moon was to obtain photographs of its far side, which can never be observed from Earth. The Television

Scientific Research Institute developed a camera for the mission; a facsimile system using film developed on hoard and scanned by a photometer for transmission. The camera was fixed and had to be pointed at the Moon by appropriately orienting and stabilizing the spacecraft, which required a З-axis pointing and control system rather than the spin stabilization used by the Ye-1 spacecraft. The Ye-2 would be the first to accomplish this vital mode of attitude control. In addition, the spacecraft had to be placed onto a trajectory that would enable it to view the far side of the Moon from a close range and under suitable illumination, and then return to the vicinity of Earth in order to transmit its pictures.

Keldysh’s Applied Mathematics Institute designed special orbits that would allow7 the spacecraft to photograph the far side of the Moon and then return to the vicinity of Earth over the USSR to transmit the pictures back at close range. There were only two launch opportunities for these restricted types of orbits, one in October 1959 for photography on approaching the Moon, and another in April 1960 for photography on receding from it. One Ye-2A spacecraft was launched in October and two of the Ye-3 type were assigned to the follow up. The first, Luna 3, was successful, but both of the more advanced spacecraft were lost to launch vehicle failures.

The Luna 3 mission was a momentous achievement for that time, and its pictures excited the w orld. But no one outside the USSR knew7 of the failures in the program. Of nine launches, six were total losses. Luna 1 failed to achieve its prime mission, but

Luna 2 was successful. And although Luna 3 look and transmitted pictures, they were of poor quality. Nevertheless, to the outside world it appeared that the Soviets had successfully launched three lunar missions of progressively greater complexity, and could do almost anything at will. In stark contrast, at the end of 1960 America appeared to be incompetent with nine embarrassing public failures yielding just one wide miss of the Moon.

After the success of Luna 3, the Soviet lunar program experienced a З-year hiatus as the focus shifted to the more challenging planetary targets, Venus and Mars, and a new robotic spacecraft was developed for soft landing on the Moon.

Spacecraft:

Two competing telecommunication systems were started for the lunar photography, one by Bogomolov labeled Ye-2 and the other by Ryazansky labeled Ye-2A. It was decided to use the Ye-2A system. The Ye-2A spacecraft designed by Gleb Maximov was a cylindrically shaped canister 130 cm in length with hemispherical ends and a 120 cm wide flange near the top. The cylindrical section was approximately 95 cm in diameter. The canister was hermetically sealed at 0.23 bar and held the cameras and film processing apparatus, communications equipment, thermal control fans, gyroscopes, and rechargeable silver-zinc batteries. Uplink was at 102 MHz and downlink at 183.6 MHz. A backup telemetry system operated at 39.986 MHz. The spacecraft had six omnidirectional antennas, four protruding from the top and two from the bottom. The thermal control system was to prevent the internal temperature from exceeding 25 C by using passive flaps mounted along the cylinder. There were micrometeoroid detectors, cosmic ray detectors, and solar cells for recharging the batteries on the exterior. The upper hemisphere of the probe housed the camera port, and the lower hemisphere housed the cold gas З-axis attitude control jets. There was no propulsion system with which to perform midcourse maneuvers. The spacecraft was to be spin stabilized under cruise, switch to 3-axis stabilization for photography, and then resume spin stabilization. Photoelectric cells were used to maintain orientation with respect to the Sun and Moon.

The follow up spacecraft, originally designated Ye-2F, were intended to acquire more and improved images of the lunar far side. As these were being prepared, there was a parallel rush to get the new’ four-stage R-7 and the Mars and Venus spacecraft ready for launch starting in the fall of 1960. The Ye-3 project was canceled when its camera system was judged too complicated and unreliable, and the Ye-2L spacecraft was re-designated Ye-3 shortly before launch. These two spacecraft were essentially the same as the Ye-2A but with improved imaging and radio systems.

Ye-2A launch mass: 278.5 kg

Payload:

1. Yenisey-2 photo-television facsimile camera system

2. Micrometeoroid detector

3. Ion traps (3)

4. Cherenkov radiation detector

5. Scintillation and gas discharge Geiger radiation counters

6. Mass spectrometer (not flown)

Several instruments from Luna 1 and 2 were flown in addition to the new camera system. A mass spectrometer based on an instrument that was flown sueeessfully on Sputnik 3 was planned but canceled owing to mass and time constraints.

Unlike the Americans who chose to use television v id icon tube cameras for their early deep space photography missions (except the Lunar orbiter series), the Soviets used a film camera system. This was mechanically complex and heavy but provided higher resolution, greater sensitivity, better quality, and was distortion free. The Yenisey-2 facsimile imaging system on the Ye-2 and -3 spacecraft consisted of a 35 mm film camera equipped with 200 mm f/5.6 and 500 mm f/9.5 lenses, an automatic film processing unit, and a photomultiplier film scanner with a resolution of L000 pixels line. The 200 mm objective was sized to image the full disk of the Moon. The camera cycled through four exposure times from 1 /200th to 1 /800th second. It exposed adjacent frame pairs simultaneously, one through each lens, and was capable of taking 40 frames at 1.000 x 1,000 pixel resolution using temperature and radiation resistant isochromatic film. The developed film could be scanned and rewound at ground command, and could be transmitted at either 1.25 lines/second or 50 lines/second depending on the range from Earth. The video signal was sent using the 3-W 183.6 MIIz transmitter. After the Cold War, it was revealed that the Soviets did not have radiation-resistant film and used US radiation-resistant film acquired by scavenging downed American spy balloons flown over the USSR from Western Europe.

Mission description:

Only the first of these missions survived its launch vehicle. The Luna 3 spacecraft (Yc-2A No. l) was successfully launched on October 4, 1959, into an elliptical Earth orbit that took it close to the south pole of the Moon, whereupon lunar gravitation redirected the trajectory back to the vicinity of the Earth, forming a figure-of-eight loop. The spacecraft, which the Soviet press dubbed the ‘Automatic Interplanetary Station’, experienced severe overheating with consequent ragged telemetry shortly after launch. This was alleviated somewhat by reorienting the spin axis and shutting off some equipment. To prepare for photography, the spin was stopped and the gyro-controlled З-axis orientation system activated. It flew within 6.200 km of the south pole of the Moon when at closest approach at 14:16 UT on October 6, and then crossed through the plane of the Moon’s orbit out over the sunlit far side. Early on October 7 the photocell on the top end of the spaceeraft detected the sunlit Moon at a distance of 65,200 km and initiated the 40 minute photography sequence. Twenty-nine frames w’ere exposed before the mechanical shutter jammed. The final image was taken at a distance of 66,700 km.

After photography w? as complete, the spacecraft resumed spinning and the first attempt was made to retrieve images. The signal strength was low and intermittent, and only one image with almost no detail was received. A second attempt was made near apogee at 470.000 km from Earth, but again the transmission quality w as poor. The antenna patterns on the spacecraft may not have been optimal. It was decided to wait for the most ideal situation when the spacecraft returned to the vicinity of the Earth ten days later. As the spacecraft approached Earth, several attempts to retrieve the images at fast playback did not yield good results. The signals were weak, with a lot of static and radio noise. To reduce the latter, Soviet engineers enforced radio silence in the Black Sea in the vicinity of the Yevpatoria receiving antenna. Finally, on October 18 the signals improved abruptly and 17 resolvable but noisy pictures were successfully received. By design, the mission was undertaken when a portion of the near side was illuminated to provide a point of reference, so only 70% of the far side was sunlit. Contact with Luna 3 was lost on October 22 and it burned up in the Earth’s atmosphere in April 1960.

Both Ye-3 spacecraft fell victim to their launchers. The third stage of the rocket carrying Yc-3 No. l cutoff prematurely. The kerosene tank had not been completely filled! At a range of only about 200,000 km from the Earth the spacecraft fell back and burned up in the atmosphere. The Yc-3 No.2 launch failed spectacularly when at the moment of liftoff one of the strap-on boosters failed to reach full thrust, placing abnormal loads on the vehicle. Three of ihe strap-ons separated at only a few meters altitude, resulting in violent maneuvers of the four separated pieces of the rocket and powerful explosions. There was considerable damage to the pad and buildings at the launch site. This brought a fiery end to the first series of Soviet lunar spacecraft and the final use of the 8K72 R-7E Luna launcher for lunar missions.

Results:

Luna 3 was the first spacecraft to photograph the lunar far side, but the 17 pictures successfully received were very noisy and of low resolution. Only six of these were published. A tentative atlas was compiled showing the far side to be very different to the near side, being predominantly bright highland terrain, without extensive mare. Two small dark regions were named Sea of Moscow and Sea of Dreams, the latter in honor of the Mechta first flyby mission.

Campaign objectives:

After the August 1964 government declaration that divided the work on the Soviet manned lunar program between Chelomey’s Proton-launched cir cum lunar program and Korolev s N-l launched lander program, Korolev continued throughout the year to argue for both to be consolidated under his ОКБ-1. In addition to organizational and economic arguments, he offered the prospect of reaching the Moon much sooner with a spacecraft already in an advanced stage of design, whereas Chelomey would have to start from scratch. For the circumlunar mission Korolev proposed a stripped down form of his Earth orbital Soyuz complex w hich, as it happened, w^as originally conceived wath lunar missions in mind. The anxiety to get a Soviet cosmonaut to the Moon first, and Korolev’s persuasiveness, won him a partial victory in October 1965 when the government approved his 7K-L1 lunar Soyuz for circumlunar flights that would be launched by Chelomey’s Proton using OKB-l’s Block D as an upper stage. The N-l was neither ready nor appropriate for circumlunar missions, it was for the manned lunar landing program. Although rivals, Korolev and Chelomey appeared to work together well in implementing this circumlunar plan. Meanwhile Korolev would continue to develop the hardware for the manned lunar landing program: the N-l launcher, the LOK lunar orbital version of the Soyuz, and the LK lunar lander.

7K-L1 No.4L

Cireumliinar and Return Test Flight

USSR TsKBEM

Proton-K

September 27. 1967 at 22:11:54 UT (Baikonur) Booster destroyed.

7K-L1 No.5L

Circumlunar and Return Test Flight

USSR/TsKBCM

Proton-K

Zond 8 (7K-L1 No.14)

Circumlunar and Return Test Flight

USSR TsKBEM

Proton-K

October 20, 1970 at 19:55:39 UT (Baikonur) October 24. 1970 October 27. 1970 at 13:55 UT Successful recovery in Indian Ocean.

It was decided to make the test flights of the lunar versions of the Soyu/ in the Zond series, beginning with the 7K-L1 circumlunar model launched by the Proton. Approved in December 1966, the plan for the LI program called for four automated tests prior to the first manned circumlunar flight, which was scheduled for launch on June 26, 1967. The follow-on series was intended to test the 7K-LOK lunar orbital model launched by the N-l lunar rocket, the Soviet counterpart to the Saturn V. This extensive flight testing in the manned program was unique to the Soviets. Ironically, Korolev generally eschewed full-up piloted flight tests in the manner of Apollo, but he abhorred the extensive ground testing the US conducted in all its programs. As a result, Soviet spacecraft generally had a much higher degree of automation than US spacecraft, often to the chagrin of the cosmonauts, and the lack of ground testing led to poor performance in test flights and consequent failures and delays.

The success of Zond 5 in circumnavigating the Moon, returning to Earth and then being recovered in September 1968 set of!’ celebrations in the USSR. It was the first mission of either nation to achieve this feat. Shortly afterwards the Soviets revealed that it was an automated flight of a Soyuz manned capsule. This set off alarms in the US, because the way seemed clear for a cosmonaut to Пу the same mission. There were windows in November and mid-December which would enable the Soviets to steal a march on Apollo 8. whose launch window was in late December. (A window Гог the northerly Baikonur site opened slightly earlier than for the lower latitude site in Florida.) The Soviets used the November window for another test, but Zond 6 Tailed catastrophically during landing. Unaware of this setback the US expected a Soviet manned circumlunar mission in December, but there was no such launch. The way was now clear for Apollo 8. The Soviets had insisted on four successful automated flights of Zond prior to a manned mission. There had been an internal debate on whether it would be justified to make an attempt as reckless as the Soviets Гек the Americans were making with a mission to orbit the Moon using the first manned Saturn V. The failure of Zond 6 rendered this debate moot. After Apollo 8 the Soviets doggedly continued to perfect Zond for the circumlunar mission, but switched their focus and rushed tests of the N-l launcher.

Although most Zond test flights were designed to provide information on the techniques and technologies needed to fly cosmonauts to the Moon and back safely, they also provided information of scientific interest. Instrumentation flown on these missions gathered data on micrometeoroid flux, solar and cosmic rays, magnetic

fields, radio emissions, and the solar wind. Biological payloads were also flown and many excellent photographs of the Moon and Earth were taken.

Spacecraft:

The Soyuz 7K-L1 was a version of the 7K-LOK lunar orbital spacecraft modified to perform a circumlunar mission. Lacking an orbital module, it would have carried two rather than three cosmonauts. It had redesigned instrument panels for lunar missions and a thicker heat shield to handle the faster re-entry from a lunar return. There were a number of other design differences for the circumlunar missions.

Zond 4 is notable for being the first Soviet spacecraft to possess a computer. The 34 kg Argon 11 used integrated circuits, drew 75 W, was capable of 15 operations, and was provided with 4K of instruction ROM and 128 words of RAM.

Zond launch mass: ~ 5,375 kg

Payload:

Zonds 5 to 7:

1. Imaging system (color on Zond 7)

2. Cosmic ray detectors

3. Micrometeoroid detectors (Zond 6 only)

4. Biology payload

Zond 8:

1. Imaging system

2. Solar wind collector

The imaging systems on Zond 5, 6 and 8 carried a 400 mm camera for 13 x 18 cm frames of lsopanchromalic film. Zond 7 carried a 300 mm camera using 5.6 x 5.6 an film, both panchromatic and color. The solar wind collector utilized aluminum foil targets similar to the solar wind collectors that xA. pollo astronauts set up on the lunar surface, except that in the case of the Zond missions they were on the exterior of the descent capsule.

Mission description:

The constraints for circumlunar flights with launch and recovery in the high latitudes of the Soviet Union were fairly severe, yielding only 5 or 6 launch opportunities per year and not always spread out evenly over the year. Hence some Zond tests were made out to lunar distance without the Moon being available. Before the automated circumlunar series, there were two Earth orbital test flights. The first, launched on March 10, 1967, was only the fifth flight of the Proton and the first with Korolev’s Block D fourth stage. It successfully placed the Soyuz into an orbit with an apogee far from Earth and telemetry tests were carried out. No recovery was attempted. The mission, designated Cosmos 146, was an auspicious start. The schedule for the first manned circumlunar flight in June 1967 seemed feasible. But then everything went wrong. The second flight test on April 6, 1967, went awry when the Block D failed.

Worse, on April 23 the first manned Earth orbital flight of the Soyuz failed when it crashed upon landing, killing cosmonaut Vladimir Komarov. His brief orbital flight had been plagued with serious problems and in attempting an emergency landing the parachute became entangled. Both the Zond and Soyuz programs stood down while the common issues were addressed. By September the Zond program was ready to resume.

The first two circumlunar mission attempts fell victim to the Proton launcher. In the first on September 27, 1967. one of the six engines on the booster failed to ignite owing to a blocked propellant line and the rocket was destroyed 97 seconds into the flight. Pad engineers had not removed a cover before flight. On the second launch on November 22, 1967. one of the four engines on the second stage failed to ignite at 125 seconds into the flight and the rocket was destroyed at the 130 second mark.

The next launch had been scheduled for a window7 in April 1968, but the Soviets were anxious to finish testing and beat the US to the Moon so it w7as decided to go early, without the Moon, and test the spacecraft to lunar distance with the high speed re-entry. On March 2. 1968, Zond 4 w7as launched into a highly elliptical orbit with an apogee al 354.000 km. ll suffered many in flight system failures. An erratic star tracker in the attitude control system complicated the flight, but engineers managed to navigate the spacecraft back to Earth. The sensor failed again in the automated re-entry sequence, resulting a ballistic rather than the intended guided descent. While descending on its parachute over the Gulf of Guinea the capsule realized that it was off course and self-destructed using a mechanism installed in part to ensure that the Americans could not recover the spacecraft in the event of a badly targeted re-entry.

The next Zond launch attempt w’as to have been a cireumlunar flight, but it failed ignominiously on April 22, 1968, when the spacecraft emergency escape system was erroneously triggered at the 194 second mark, shutting down the second stage of the launcher and carrying the Zond spacecraft clear. It was recovered 520 km from the pad. Another planned Zond launch w? ent awry on July 14, 1968. when the oxygen tank in the fourth stage ruptured on the pad during pre-launch testing, destroying the Block D stage and killing three engineers. Fortunately, the lower stages, all loaded with propellant, did not explode. Although undamaged, spacecraft 7K-L1 No.8 was discarded.

After this frustrating series of failures, Zond 5 became the first fully successful cireumlunar flight. Launched on September 14. 1968, it achieved its mission despite suffering several technical problems. The Earth sensor had been mounted incorrectly owing to an error in the documentation. The star-tracker attitude control system was rendered ineffective when its optical surfaces became contaminated by sublimating thermal protection material. Worse, the backup system was mistakenly turned off. But engineers were able to control the spacecraft’s attitude in an awkward and slow’ process using the Sun sensors. Two midcourse maneuvers were conducted, and the spacecraft flew7 around the Moon on September 18 with a closest point of approach at an altitude of 1,950 km. Jodrell Bank announced the achievement and reported the spacecraft heading back to Earth. Only at this point did the Soviets actually admit to having launched the mission! On the voyage home a second attitude control sensor failed. On September 21 the spacecraft re-entered at 11 km/s at an overly steep angle on a ballistic rather than the planned guided ‘skip’ re-emry. fortunately, after the loss of Zond 4, the self-destruction system had been deleted. After a 6 minuie ride through the atmosphere with peak stresses of 16 G and 13.000 C, the descent capsule parachuted into the Indian Ocean at 16:08 UT near 32.63’S 65.55’E. 105 km from the nearest Soviet tracking ship. This was the first water recovery for the Soviets. The eapsule was offloaded at Mumbai. India, for return lo Moscow by aircraft. This boosted Soviet confidence in their human lunar program, but the flight had suffered serious non-fatal failures.

Zond 6 was successfully launched on November 10. 1968. Attitude control again became a problem when the high gain antenna, with the main star tracker attached. Tailed to deploy. The backup siar tracker system and a lower gain antenna were used instead. As the spacecraft flew around the Moon on November 14 at an altitude of 2,420 km it photographed the near and far sides. On its way home engineers had to reorient the spacecraft to try to control the temperature in a hydrogen peroxide tank by exposing it to direct sunlight and unfortunately this also heated and deformed the hatch seal, causing the cabin to depressurize. The biology payload was killed and the altimeter damaged. In preparation for re-entry on November 17 the service module separated as intended but the high gain antenna remained attached to the front of the capsule. The vehicle entered the atmosphere at 11 km/s and after bleeding off some energy it skipped back into space at 7.6 km/s as intended, at which time the antenna detached. All went well with the ‘second dip’ until at an altitude of 5,300 meters the altimeter failed to function properly and commanded the parachute to be jettisoned. Some film was recovered from the wreckage, including the first color pictures of the Moon, before explosives engineers detonated the 10 kg of I N I that had been carried on board the capsule for the radio-command destruct system.

Of tw o circumlunar missions, Zond 5 had failed to perform the skip’ maneuver during re-entry and had made a ballistic descent and splashed into the Indian Ocean, and Zond 6 had flown the intended trajectory only to fail on its parachute within the Baikonur boundary only 16 km from the launch pad. Undeterred, the Soviets made a valiant effort to prepare a mission for the December opportunity. Cosmonauts in training for a circum lunar flight argued to be allowed to fly. A vehicle was rolled out to the pad on December 1. but the spacecraft suffered so many technical problems that the window closed before approval to launch could be obtained. Even after the successful flight of Apollo 8 later in the month, the Soviets continued with the Zond tests. The hardware was available and the obvious thing was to push for success and realize the benefits of the investment. There was no precedent for actually stopping a Soviet space project with this much visibility. There remained the hope of making a manned circumlunar flight, although this prospect faded as the focus switched to the N-l launcher.

But in the next 8 months, w hile the Americans reveled in the success of Apollo 8, 10 and 11. three more set backs were to plague the Soviet manned lunar program. Anxious to solve the problems with the Zonds, another test flight to lunar distance was planned before the circumlunar window’s opened in summer. The launch of 7K – L1 No. l3L failed in January 1969 due to problems with the second and third stages.

One of four sccond-stagc engines shut down early, and then during its phase of the ascent the third stage suffered a breakdown in its fuel feed system and cut off. Even more significant for the manned program, in February and July of 1969 the first two test launches of the N-l lunar rocket also failed.

Nine months after the Zond 6 disaster, and shortly after Apollo 11 succeeded and the Soviet robotic lander Luna 15 crashed, Zond 7 was launched towards the Moon on August 7, 1969. The next day, it conducted a midcourse maneuver and took color pictures of Earth. On August 11 the spacecraft flew around the Moon at an altitude of 1,985 km and performed two sessions of color photography of both the Moon and Earth. It returned to Earth on August 14, made the intended ‘skipping’ re-entry and landed successfully in a preselected area south of Kustanai in Kazakhstan.

The plan had called for four test flights prior to a manned circumlunar mission, but of the four only Zond 5 and 7 wrere fully successful. This poor success rate led to

a proposal to fly one more test flight and then a manned mission to celebrate Lenin’s birthday in April 1970. The supporters argued that the flight would contribute to the program by demonstrating to the world that the USSR was capable of manned lunar missions. But the government rejected it because it would look second rate. To have sent cosmonauts on a circumlunar mission ahead of Apollo 8 would have been one thing, but to do so after Apollo 11 was something else. At the political level, benefit was now being determined relative to American achievements. Approval was given only for the final automated test flight.

Zond 8 vras launched on October 20, 1970. The next day it took pictures of Earth

from 64,480 km, and the day after that it made a midcourse maneuver at a range of

250.0 km. ft transmitted images of Earth for 3 days during its outbound flight and conducted two imaging sessions as it passed behind the Moon on October 24 at an altitude of 1,110 km. After two midcourse correction maneuvers on the return leg, it made a ballistic re-entry over the northern hemisphere on a southbound trajectory to sustain communication in most of the re-entry sequence. All previous Zonds had re­entered over the southern hemisphere, heading north. The capsule splashed into the Indian Ocean at 13:55 UT on October 27, approximately 24 km from the target point 730 km southeast of the Chagos Islands. It was recovered 15 minutes later by the Soviet oceanographic vessel Taman for return to Moscow by way of Bombay, India.

Results:

These were primarily engineering tesl flights, but they also carried payloads which provided scientific results.

Zond 5: High quality photographs of Earth were taken on the way home at a range of 90,000 km. They were useful because the film would be able to be processed on Earth rather than scanned on board and transmitted by radio. A biological payload of turtles, wine flies, fly eggs, meal worms, plants, seeds, bacteria, and other

living matter was recovered. The turtles had lost significant body mass and exhibited other metabolic anomalies. The fly eggs had not produced the expected number of adults, and the next generations of these showed a large increase in mutations.

Zond 6: The crash broke the film canister, but some film was recovered including images of the lunar limb and far side features taken at ranges of approximately 3,300 to 11,000 km. Some stereo pairs were also obtained. Only a few of its images have been published.

Zond 7: Color photography of both Earth and the Moon. A biological payload of turtles, wine flics, meal worms, plants, seeds, bacteria, and other living matter was successfully recovered.

Zond 8: Obtained photographs of Earth and the Moon from distances of 9,500 and 1,500 km.

To sum up, although the photography was excellent the science results from these

test flights were minimal. Data on solar wind and cosmic rays was obtained but not published. The seed samples on recovered flights all showed chromosomal damage but of the animals only the turtles on Zond 5 showed any ill-effects.

The Venera 7 landing on the surface of Venus was a jubilant success for the Soviets. Once the pressure and temperature at the surface were finally confirmed, the NPO – Lavochkin engineers scaled back the pressure design limit from 180 bar to 105 bar and used the saved mass for a stronger parachute and more scientific instruments. In
anticipation of their next generation of larger more complex Venus landers, a photometer was added to determine the illumination at the surface. All of the previous entry probes had been targeted at the night-time hemisphere, mainly to ensure direct-to-Earth comm uni cations. but day-side light-level measurements were required in order to design imagers for future landers. So the 1972 missions were to land in early morning daylight at sites near the terminator from which it would still be possible to transmit to Earth. A redundant deployable antenna was ineluded as a precaution against poor primary antenna pointing or obscuration of the line of sight by rough terrain.

Two launches were attempted, the first successfully dispatching Venera 8 and the second stranding its spacecraft in parking orbit. Venera 8 was the ultimate success of the 3MV series and. as events transpired, the last of its type. It achieved all that the Soviets had worked so hard for over so many years and so many attempts. It was the final reward for dogged persistence. During its construction, NPO-Lavochkin was working on the new generation of Luna spacecraft to undertake sample return, rover and orbiter missions, and the or biters and landers for Mars, both of which would use the Proton launcher, so this was the final planetary campaign to employ the 8K78M Molniya.

Venera 8 supplied the data needed to design the much more sophisticated landers that would be delivered by the next generation of advanced Venera spacecraft to be launched by the Proton rocket beginning in 1975.

Spacecraft:

The carrier spacecraft for Venera 8 was essentially the same as for all missions since Venera 4, but the entry probe was modified. The pressure design limit was reduced to accommodate additional science instruments and the parachute was strengthened, although the size of the canopy was the same as for Venera 7 in order to make the same rapid descent through the atmosphere. Since the probe was to land further from the center of the planet as viewed from Earth, the antenna transmission pattern was changed from the egg-shape that was appropriate when Earth was at the zenith to a funnel-shape for when Earth was low on the horizon. In case the capsule were to come to rest on its side, a second antenna was provided that was to be ejected onto the surface and this was a flat disk with a spiral antenna on each side to enable it to work irrespective of how it settled.

A new honeycomb composite material was used as the primary insulation of the lander. Further thermal protection was provided by using lithium nitrate trihydrate, a phase-change material that absorbs heat by melting at 30’C. In addition to forming ‘thermal accumulators’ inside the pressure vessel, this jacketed the instruments that projected outside.

Launch mass: 1,184 kg

Entry capsule mass: 495 kg

Payload:

Carrier spacecraft:

1. Solar wind charged particle detector

2. Cosmic ray gas discharge and solid state detectors

3. Ultraviolet spectrometer for Lyman-alpha measurements

Descent I landing capsule:

1. Temperature, pressure and density sensors

2. Atmospheric chemical gas analyzer

3. Broad-band visible photometers (2)

4. Gamma-ray spectrometer

5. Radio altimeter

6. Doppler experiment

An accelerometer was to measure atmospheric density during the descent prior to parachute deployment. The altimeter had been redesigned to provide an accuracy of several hundred, meters for the instruments that would operate during the parachute descent. The atmospheric composition experiment now included an ammonia litmus

test, and the atmospheric structure experiment carried four resistance thermometers, three aneroid barometers, and a capacitance barometer. A pair of single-channel broadband cadmium sulfide photometers were carried to measure the integrated downward flux with a 60 degree field of view in the wavelength range 0.52 to 0.72 microns. The optical unit was outside the capsule, mounted on top inside a separate unit scaled against high pressure and insulated against high temperature. The light reached the electronics by a 1 meter long light guide of fiber optic. The photometers were sensitive over the range 1 to 10,000 lux and encoded logarithmically.

The gamma-ray spectrometer was mounted inside the hermetically sealed probe. It was sensitive to emissions from potassium, thorium and uranium, and had been calibrated for these elements against a suite of Earth rocks.

Mission description:

Venera 8 was launched on March 27, 1972, made its midcourse correction maneuver on April 6, and arrived at Venus on July 22. The solar panels charged the batteries of the capsule and a system in the cruise module pre-cooled the capsule by circulating air through it at -15C’C. After being released 53 minutes prior to entry, the capsule hit the atmosphere at 11.6 km/s at 08:37 UT at an angle of 77 degrees on the sunlit side.

approximately 500 km from the morning terminator. Eighteen seconds later it had slowed to 250 m/s and deployed its pilot parachute. The reefed main parachute opened at 60 km altitude and the canopy was fully opened at 30 km. The instruments were activated at 50 km and transmitted data during the 55 minute descent. There was a clear line of sight to Yevpatoria. The capsule thumped onto the surface at 10.70°S 335.25°E. It was 6:24 Venus solar time and the solar zenith angle was 84.5 degrees. The parachute was jettisoned on impact and the secondary antenna was

deployed onto the surface. The capsule transmitted for another 63 minutes reporting measurements on the surface, starting with a 13 minute stream from the primary antenna, then a 20 minute stream from the secondary antenna, and finally a 30 minute stream from the primary.

The Venera 8 carrier spacecraft returned measurements on the upper atmosphere and ionosphere prior to breaking up in the atmosphere.

The second spacecraft to be launched failed to depart from low Harth orbit due to a fourth-stage misfire when the failure of a timer caused the engine to stop after only 125 seconds. It was stranded in a highly elliptical orbit and designated Cosmos 482. At the end of June a fragment separated. This was probably the entry capsule, and it remained in orbit when the main spacecraft re-entered on May 5, 1981.

Results:

The Venera 8 capsule returned a wealth of data about the atmosphere and surface. It determined atmospheric density from accelerometer data in the altitude range 100 to 65 km and directly measured atmospheric temperature, pressure, composition and down-welling light flux from 55 km down to the surface. Although imprecise, these first profiles of the solar flux versus altitude were sufficient to confirm that the high temperatures were caused by the greenhouse effect. The illumination at the surface was measured and the pattern of change in attenuation attributed to clouds. Profiles of the speed and direction of horizontal winds from 55 km down to the surface were obtained from Doppler data. The wind speed was 100 m/s above 50 km, 40 to 70 m/s in the haze layer near 45 km, surprisingly rapid at 20 to 40 m/s below this down to 20 km, and only about 1 m s from 10 km to the surface. The wind was super-rotating coincident with the motion of the high ultraviolet clouds.

The first report from the radio altimeter was at an altitude of 45.5 km and it gave a total of 35 readings, the last at 900 meters. The capsule drifted 60 km horizontally as it descended. The altimeter produced a ground profile with two mountains 1,000 and 2,000 meters tall, a hollow 2.000 meters deep, and a gentle upward slope toward the landing site. Two echo intensity profiles were obtained from which it w as possible to compute the dielectric constant and a surface density of 1.4 g/ec. The photometers made 27 measurements, and the light level declined steadily from 50 to 35 km as the probe descended through the clouds. Venera 8 was the first to distinguish three main optical regions in the atmosphere: two cloud layers w’ith a thicker upper layer of fog from 65 to 49 km and a lower haze layer from 49 to 32 km. Then the light level was essentially constant to the surface, indicating a relatively clear atmosphere below the clouds. The illumination in this part of the atmosphere was comparable to a cloudy day on Harth at tw ilight. The w eak surface brightness indicated that only 1 % of the incident sunlight reached the surface. On the other hand, the Sun was only 5 degrees above the horizon. The important finding was that the illumination wras sufficient for the next lander to operate a camera.

The gas analyzer returned a composition of 97% carbon dioxide, 2% nitrogen.

0. 9% water vapor, and 0.15% oxygen. Although the ammonia test gave a positive detection at altitudes between 44 and 32 km with readings of 0.1 to 0.01 %. this was compromised by sulfuric acid which also reacts positively. A significant point is that the gas analyzer eon firmed the presence of sulfuric acid in the clouds. This had been offered as an explanation of why the clouds were so arid and yet were able to form cloud droplets. And the fact that such droplets would reflect sunlight so efficiently explained why the planet had such a high albedo.

On the surface, Venera 8 reported a pressure of 93 + 1.5 bar and a temperature of 470 ± 8’C. confirming the measurements by Venera 7 and in good agreement with an extrapolation of the data from the Venera 4, 5 and 6 probes down to the surface using models of the adiabatic temperature lapse rate.

The gamma-ray spectrometer made measurements in the descent, and tw o on the surface. It reported 4% potassium. 6.5 ppm thorium, and 2.2 ppm uranium indicative of a more granitic than basaltic composition. However. this result was contested and all later Venera landers found more common basaltic compositions. Radar mapping many years later showed that Venera 8 landed in an upland volcanic region that was probably older than the lava plains that constitute most of the planet. Alternatively, a potassium-rich basalt that is relatively rare on Earth could account for this particular data.

A HISTORICAL SYNOPSIS

The history of exploring the Solar System by spacecraft is short, spanning less than 42 years at the end of the 20th Century. Prior to January 1,2001, there had been 182 launches. Of these, 89 were successful or partly successful, and three were in transit to their ultimate destinations. The exploration of the planets was dominated in the 20th Century by competition between the USSR and USA. Only five of the total of 182 missions were developed by other parties. It was not until 1985 that Europe and Japan launched their own deep space missions.

In the early years of the space race the USSR was usually first to achieve major feats at the Moon, Venus, and Mars. After the ncck-to-neck race to the Moon in the 1960s, and its culmination with Apollo, the US, which had also had greater success with planetary missions, assumed the leading position in robotic exploration in the 1970s with unopposed successes at Mars, Mercury, and the outer Solar System. The USSR had no answer to the Mariner 9 Mars orbiter, the two Viking orbiters and landers at Mars, the Mariner 10 flybys of Mercury, or the Pioneer 10 and 11 and Voyager 1 and 2 missions to the outer planets – a realm where the Soviets were not technologically prepared to go. The US had conceded only Venus, where the Venera missions reigned supreme. At the beginning of the 1980s the Soviet program could be said to have won the competition at Venus, but lost it everywhere else. This trend changed with the Vega missions in the middle of that decade. The USSR vigorously participated in the International Halley Mission with the European Space Agency and Japan, and contributed two spacecraft as platforms for instruments from any country that wished to provide them. The Europeans and the USSR led this highly successful and precedent-setting enterprise for the Old Continent. The Americans of the New World were a minor player and did not even send a spacecraft to Halley for this first world-wide planetary exploration endeavor.

By the mid-1980s, the Soviets had seized the lead in planetary exploration from the Americans. The USSR gained a great deal of pride and prestige around the world from the Vega missions to Comet Halley, and decided as a matter of policy to open

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© Springer Science+Business Media, LLC 2011 up future missions to international participation. They would be essentially Russian vehicles and Russian-led missions, but with instruments and scientific participation from around the world. The Americans were at a significant disadvantage in this situation, since they did not have the massive spacecraft to offer valuable instrument real estate to others and to compete with the Russians in this way. In addition, the US planetary program wras suffering from a major decline in the 1980s starting with the administration of Ronald Reagan, who preferred a more direct competition with the Soviet Union.

The Vega campaign had been conceived as an almost entirely Soviet mission with some participation by the French, but was modified with international instruments, many from the Eastern Bloc, being added for the Halley intercept. The next Soviet planetary mission, Phobos. was internationalized earlier in its development, look this to a greater extreme, and had more instruments of Western origin. Mars-96 was the culmination of the international style of Soviet planetary missions, with instruments openly and broadly solicited from around the world and with a larger investment by Western countries including the US. It is supremely ironic that the Americans, who prided themselves on the openness of their space exploration program, remained far more xenophobic in their planetary exploration program than the Soviets, and were obliged to concede the lead in international planetary exploration missions to the Vega, Phobos and Mars-96 missions.

After the fall of the Soviet Union in 1991, attempts to form partnerships between the US and Russian planetary programs failed as the resources for further Russian planetary missions dried up in major national economic problems. The abysmal loss of Mars-96 created an international disaster, demoralized the national program, and embarrassed the post-Soviet Russian national government and its new space agency. Already beset with financial problems, Russia cut its investment in space science missions. At the end of the 20lh Century, the Russian national program of robotic planetary exploration appeared to have been postponed indefinitely.

Unfortunate fate has been a bedfellow to Russian history for a millennium, and so it was for the Russian planetary exploration program just as it reached its peak in the late 1980s while that of the US was declining. A decade later there w? as no Russian planetary exploration program, the IJS program was revitalized, and the French, a bell-weather for international involvement in space science and a participant on Soviet missions since the early 1970s. were now making trips to Washington instead of to Moscow. But the hopes and dreams remained alive in Russia. After watching from the sidelines since 1996. and contributing primarily by offering launch services for cash, the Russians are just now emerging after a 15 year absence with the launch of a Phobos sample return mission scheduled for 2011 and with plans for a lunar orbiteriander missions for later in the decade.

Afanasyev, Sergey Aleksandrovich 1918-2001 ‘

First Minister of General Machine Building 1965-1983

Sergey Afanasyev’s organization managed the institutions and workforce that built ballistic missiles and satellites vital to the defense of the Soviet Union, as well as the spacecraft and launch vehicles for their politically important space ex­ploration program. Leonid Brezhnev once told him,

“We believe in you, but if you fail w;e will put you against a brick wall and shoot you.” Known as “the big hammer”, he could be a very rude and intimidating man but he had a talent for orches­trating immense projects. He was among the most powerful people involved in the USSR’s space program, which included Korolev and his rival Glushko. His criticism of Korolev’s management of the manned space program resulted in the separation of the robotic program from Korolev’s bailiwick to that of Georgi Babakin in 1965. He oversaw the Soviet Union’s response to the Apollo project and was ultimately responsible for canceling it after many setbacks.

LUNAR SPACECRAFT

Russian lunar spacecraft can be divided into families according to their evolution from the very first simple flyby and impactor spacecraft in 1958-1960, exemplified by Luna 1 to 3, to the first modular designs built for soft-landing culminating with Luna 9 and 13, to the final series of complex sample return and lunar rover missions beginning with Luna 15 and continuing through to Luna 24. After the first success at soft-landing, some of these spacecraft were modified to carry lunar orbital payloads, in particular to perform tasks in support of an eventual manned lunar landing. These modifications were easily and quickly accomplished because of the modular design. The final series were essentially large soft-landcrs with interchangeable payloads. Although they were complex, they achieved the first robotic sample return missions and first lunar rovers in addition to a pair of orbiters.

Luna Ye-1 series, І958-1959

in the summer of 1958, the Americans and the Russians were racing to launch the first spacecraft to the Moon as a major signal of strength in rocket technology. The spacecraft were small and lightly instrumented and were flown opportunistically on what were mainly test flights of military rockets. The goals were more technological and political than scientific.

The Americans tried eight times to reach the Moon without success in 1958 1960. Only one spacecraft, Pioneer 4, was launched successfully to Earth escape velocity, but it missed the Moon by a wide margin.

To counter the American lunar campaign, the Soviet Union built the Ye-1 lunar impactor spacecraft for launch on a new’ three-stage Luna rocket derived from the R-7 that launched Sputnik. The Yc-1 wras a very simple spherical payload similar to Sputnik, spin-stabilized, with several protruding antennas. Six such spacecraft w’crc launched during the 12 months between September 1958 and 1959. All but two were

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lost to launch vehicle mishaps, but owing to the Soviet way of not naming a mission until it was successfully underway, these were Luna 1 and Luna 2. Although Luna 1 missed the Moon on January 4, 1959, it was the first spacecraft to achieve escape velocity – two months before Pioneer 4. The final spacecraft to be launched in this series, Luna 2, became the first spacecraft to impact the Moon on September 14, 1959. Tn effect, the Soviets had kept launching until their goal was achieved, and then they moved on.

TIMELINE: OCT 1960-FEB 1961

The Moon had been the principal target for the USSR in 1958 and 1959, and for the US as well through 1960, hut both had ambitions to send spacecraft to the planets. Venus was the closest and most accessible, but Mars, slightly farther away, was the most fascinating. Having been successful at the Moon, the Soviet Union was ready to start launching planetary missions in 1960. The US, struggling to achieve success at the Moon, decided to put off attempting planetary missions.

Korolev developed a four-stage version of the R-7 rocket to launch missions to the planets, and a spacecraft quite different from the initial Luna series to meet the challenges of interplanetary flight. The new rocket and spacecraft were ready for the launch opportunities for Mars in late 1960 and for Venus in early 1961. The first attempts to send a spacecraft to Mars were on October 10 and 14, 1960. and in both cases the third stage failed, giving the new fourth stage and spacecraft no chance to perform. Later on February 4, 1961, the first attempt to send a spacecraft to Venus was foiled when the engine of the new fourth stage failed to ignite. Finally, on its fourth launch on February 12, 1961, the new rocket succeeded in sending its payload on a trajectory towards the planet Venus. Unfortunately, the Venera 1 spacecraft had a number of problems and failed early in its flight.

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THE FIRST LAUNCH TO MARS: 1960

TIMELINE: DEC 1968-APR 1970

The flight of Apollo 8 in December 1968 marked the beginning of the end for the Soviet Union’s campaign to put cosmonauts on the Moon. The Zond circumlunar flight test series had been plagued by problems. Even the successful flight of Zond 5 suffered so many subsystem anomalies that engineers were very reluctant to trust a spacecraft to a manned mission. The crash of Zond 6 made beating Apollo 8 to the Moon almost impossible, and the circumlunar program endured a further setback on January 20, 1969, when the next Zond test flight fell victim to yet another launcher failure. Any chance that cosmonauts could reach the Moon in competition with the Americans was dealt a severe blow on February 21, 1969, when the counterpart of the Saturn V, the N-l, failed spectacularly on its maiden flight. It had been intended to deliver a modified Zond into lunar orbit. The second attempt to qualify the N-l on July 3, 1969, less than a fortnight ahead of the launch of Apollo 11, resulted in the biggest explosion in the history of rocketry and destroyed the pad facilities. The last of the scheduled Zond flight tests, Zond 7, was a success in August, 1969, but by then the race was over. Instead of following up with a manned circumlunar mission the Soviets added another automated flight, which flew successfully in October 1970 as Zond 8. After two further attempts to qualify the N-l in June 1971 and November 1972 also failed, the manned lunar program vras canceled.

However, the Soviets countered the Apollo program with a series of robotic lunar missions using a new, large spacecraft that was originally designed to land a rover for a cosmonaut to employ on the lunar surface. When in late 1968 and early 1969 it became clear that the Americans were likely to beat them to the Moon, the Soviets opted to use this robotic landing system to try and upstage Apollo by being the first to return a lunar sample to Earth.

While the sample return system was being developed for use with the lander, the first launch of the new’ lander with a rover was attempted on February 19, 1969, but it was lost when the payload shroud failed shortly after the Proton launcher lifted off’. The first sample return spacecraft was launched on June 14, but lost when the

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fourth stage failed. Rushing to beat Apollo 11 to the Moon, another sample return mission was launched on July 13, 1969, ten days after the devastating N’-l explosion and 3 days before Apollo 11 was launched. This spacecraft, Luna 15, successfully reached lunar orbit 2 days ahead of Apollo 11 and Westerners, uninformed of its intentions, viewed it with suspicion. Shortly after the lunar module of Apollo 11 set down on the Moon on July 20 and its astronauts made their historic moonwalk, the Soviet spacecraft crashed attempting to land in the Sea of Crises, some distance cast of the Apollo 11 site in the Sea of Tranquility. The next three attempts through the middle of 1970 to return samples from the Moon with this type of spacecraft were all lost to launch vehicle failures.

In early January 1969 the Soviets followed up their 1967 success at Venus with two launches of spacecraft similar to Venera 4 but modified to descend through the atmosphere more rapidly, and thereby provide data from deeper levels than before. Although Venera 5 and Venera 6 worked well, they imploded far above the surface.

The Soviets were ready with a new spacecraft designed for Mars in March 1969. Like the new Luna for delivering rovers and sample return spacecraft, these were heavy spacecraft that needed the Proton launcher. They had been designed Lo be able
to enter orbit around Mars and dispatch a lander, but for the 1969 window they were to release a probe to get the data on the atmosphere that was required to design that lander. When the probe was deleted owing to development and test problems it was decided to equip the two spacecraft for this window as orbiters. Neither survived its launcher. These spacecraft and their launch attempts were virtually unknown in the West until after the Cold War. Blissfully unaware of this potentially overwhelming competition, the IJS dispatched two more flyby missions to Mars in 1969, Mariners 6 and 7, both of which were successful.