Category Soviet Robots in the Solar System

By early 1974 the Soviet space program was severely traumatized. Its manned lunar program had failed both to beat the IJS to a circumlunar flight and to introduce into service the N-l, its answer to the Saturn V launcher, meant to dispatch cosmonauts to land on the Moon. It had taken second prize with robotic lunar rovers and sample return missions. The all-out Mars effort of 1973 had been an embarrassing failure. In May, Vasily Mishin. Sergey Korolev’s protege and successor, was replaced as Chief Designer by the avowed rival to both, Valentin Glushko, who canceled the N-l and refocused the manned program on a new Energiya launcher and the Buran reusable spaceplane to compete with the space shuttle the US had recently started to develop.

In the early 1970s a "war of the worlds’* had raged in the community of Soviet scientists and engineers working on planetary exploration. The Venusians’ argued for concentrating on Venus where they felt the USSR had a clear advantage, instead of challenging the US wiiere it had gained the advantage. Of course, the "Martians* argued to focus on Mars as the more interesting of the tw o planets. They could not compete with the sophisticated Viking landers, but studies had been underway for several years for a bold and even more prestigious mission to Mars a sample return that w ould require the N-l lunar rocket. The debate w as between Roald Sagdeev, the Director of IKI, and Alexander Vinogradov, Director of the Vernadsky Institute of Geochemistry. Vice President of the Academy of Sciences and Chair of the Lunar and Planetary Section of the Academy’s Inter-Department Scientific and Technical Council on Space Exploration. The ultimate arbiter w;as Mstislav Keldysh, who was scientifically the most acknowledged and most politically well connected member of the community. Keldysh hesitated over the very ambitious plans of the "Martians* and eventually took the practical route by turning to Venus for the immediate launch opportunities. NPO-Lavochkin was allowed to continue designing Mars rovers and sample return missions that w’ould use the Proton launcher, but by 1975 76 these w ould prove impractical. Instead, Sergey Kryukov, who had taken over from Gcorgi Babakin on the latter’s death in August 1971, proposed to salvage the Mars program with a less ambitious mission to Phobos, the larger of the planet’s two small moons. Keldysh w’as supportive of this concept, but it w ould fade after Kryukov resigned in 1977 and Keldysh died in 1978, and the ‘Martians* had to stand down wiiile Venus look center stage for the next ten years.

Nonetheless, it is interesting to describe in some detail the very ambitious plans of the ‘Martians’ at that time. Soviet engineers had been working on designs for Mars sample return missions in parallel with developing the Mars spacecraft for the 1971 and 1973 campaigns. Bolstered by the success of the Luna 16 sample return and the Luna 17 lunar rover missions in 1970, the “top brass” ordered NPO-Lavochkin to fly a Mars sample return mission by mid-decade. Kryukov assumed that the N-l would be available. The first spacecraft design had a launch mass of 20 tons. The 16 ton entry system used an 11 meter acroshell with folding petals to enable it to fit inside the payload shroud. The lander eschewed parachutes and used large retro – rockets to decelerate. A direct return to Earth was planned with a spacecraft based on the 3MV design of Venera 4 to 6, using a two-stage rocket and an entry capsule which would deliver 200 grams of Martian soil to Earth. The Soviets w’restlcd with the complexity of the spacecraft system and also with the issue of biological contamination of Earth. A test mission was tentatively planned for 1973 that would deliver to the surface of Mars a rover based on the successful Lunokhod.

The failure of the N-l rocket program forced a change to a less massive design. In 1974 NPO-Lavochkin began to consider how to use the Proton to accomplish a Mars sample return mission. Two Protons would be used. The first would place a Block D upper stage and the spacecraft into Earth orbit and the second would orbit a second Block D that would rendezvous and dock. The two propulsive stages would then be fired in succession to send a flyby /lander spacecraft to Mars. Spacecraft mass would be saved by not requiring the sample return vehicle to fly directly back to

Earth but instead to enter Mars orbit, where it would rendezvous with an Earth – return vehicle that had been launched by a third Proton. And in one scenario, instead of entering the atmosphere the return vehicle w ould brake into a low Earth orbit for retrieval by a manned mission. Again a precursor mission for landing a rover on Mars w? as planned.

The project wrestled with continuing issues of complexity and mass. This led to a refinement in 1976 in which the first spacecraft would be launched into Earth orbit with its Block D upper stage dry, so as to allow’ for increased spacecraft mass. The second launch would deliver both a second Block D and fuel for transfer into the dry stage. The flybv/lander spacecraft launch mass was 9,135 kg. The flyby spacecraft w7as 1,680 kg, and the entry system 7,455 kg including 3,910 kg for the two-stage surface-to-orbit vehicle and 7.8 kg for the Earth return capsule, which in this version would pass through the atmosphere without having either a parachute or a telemetry system. The struggle to accommodate the complexity, cost and risk of this mission strained Soviet technology beyond its limits. At the same time, NPO-Lavochkin was continuing to mount complex lunar rover and sample return missions through 1976. The results from the considerable funds that were expended on designing these Mars missions were disappointing. Other programs, including a Lunokhod 3 mission, had to be sacrificed. When it became apparent that the project w? as impractical, it w’as canceled and Kryukov was transferred.

While successful at automated lunar sample return, the Soviet Union never got the chan ее to try a Mars sample return mission. In the mid-1970s the space ambitions of both nations were thwarted by their respective governments. In addition to losing the race to the Moon the Soviets had suffered appalling failures at Mars. Performance and cost became serious issues, and risk was less tolerable. Ironically, the result in the US w7as the same despite the success of the Apollo program and the Vikings at Mars. It would be a long time before either nation sent another mission to Mars but once again it w’as the Soviets who were the first to do so, with the Phobos missions of 1988. In the meantime, having taken the lead in planetary exploration in the 1970s by exploring from Mercury to Neptune, America fell behind again in the 1980s as their planetary launch rate dropped to zero and the Soviets reaped success after success at Venus and opened up their program to international cooperation with complex science-dense missions at Venus, Halley’s comet, and finally Mars.

The Phobos-Grunt spacecraft embraces the latest in space technology and erases the tradition of pressurized planetary spacecraft. The launcher will be the Zenit-Fregat. The Zenit rocket is a legacy of the Energiya-Ruran program, and the Fregat stage is a legacy from the Phobos and Mars-96 missions. For Phobos-Grunt to achieve the desired interplanetary trajectory, a burn of the spacecraft’s engine will be required after the Fregat burns out. The spacecraft will make the mideourse maneuvers, orbit insertion, and orbital maneuvers to rendezvous w ith and ultimately land on Phobos. the larger of the two Martian moons. Tradition also survives in the boldness of Russia’s return to robotic exploration: not just a modest step but an ambitious sample return mission, which seems appropriate for a program amongst whose unanswered legacies is a sample return from the Moon. Phobos-Grunt also continues the legacy of international cooperation, because it wall carry the first Chinese Mars spacecraft, Yinghuo 1, and release it into orbit around the planet.

The main goal of the Phobos-Grunt mission is to return a sample from Phobos to Earth for in-depth laboratory studies to help to answer key questions concerning the origin and evolution of the Solar System. The payload also includes instruments for navigation and for studying the Martian environment (television, space plasma and magnetic field detectors, and a dust particle detector) and instruments to study the surface of Phobos following the landing. The latter include a panoramic camera, gas

chromatograph, gamma-ray spectrometer, neutron spectrometer, laser time-of’-llight mass spectrometer, secondary ion mass spectrometer, infrared spectrometer, thermal detector, long-wave subsurface radar and a seismometer. The robotic manipulator to be used for sampling carries a micro-television camera, an alpha, proton and x-ray spectrometer, and a Mossbauer spectrometer.

The Soviet lunar and planetary exploration program in the 20th Century left a legacy of scientific results and new knowledge. Tt is difficult to remember how little we knew about the Moon and planets at the beginning of the space age in 1957, and how much wc have learned as a result of sending out spacecraft. Table 21.1 provides a summary of the exploration milestones achieved by the Soviet program, most of which occurred during the first 15 years of the space age. Soviet scientists also made many scientific discoveries in the course of their missions. The early Luna missions established that whereas ihc near side of the Moon is dominated by the dark maria.

the far side is dominated by the bright highlands, an interesting dichotomy that has yet to he adequately explained. Lunar mass coneentrations were first discovered by Soviet spacecraft. Much of what we know of the atmosphere and surface of Venus eoincs from the Venera missions. And while the Soviets were thwarted at Mars, they were first to successfully land (albeit the lander failed after a few seconds), made the first in-situ measurements in the Martian atmosphere, the early discoveries about its ionosphere, and the lack of an intrinsic magnetic field.

The Phobos-Crunt mission represents a hope that Russia will resume a lunar and planetary exploration enterprise with the same boldness, innovation, and persistence that they demonstrated in the first 40 years of space exploration.

Keldysh, Mstislav Vsevolodovich 1911-1978

President, Soviet Academy of Sciences 1961-75

While Sergey Korolev was the engineering genius behind the Soviet space program, Mstislav Keldysh was its scientific genius and his eager partner. 1’here was no single person equivalent to Keldysh in the US space program. As a brilliant and elegant mathematician, he was particularly adept at apply­ing mathematics to complex practical problems, with a special interest in aerodynamic engineering.

From 1946 to 1961 he was head of the research organization NII-1, which is now the Keldysh Research Center. NII-1 was originally Korolev and Glushko’s rocket research group prior to their arrest in the purges. In 1953 Keldysh was named head of the Division of Steklov’s Mathematical Institute which in 1966 became the Institute of Applied Mathematics and now bears his own name. In 1961 he was elected President of the Soviet Academy of Sciences.

Keldysh’s involvement in space research began in 1954 when he co-chaired with Korolev the committee that designed the scientific spacecraft that ultimately became Sputnik 3. Beginning in 1956 he chaired the Academy’s powerful MNTS committee and was regarded as the ‘Chief Theoretician’ of the space program, in charge of the scientific aspect of space including military applications in computers and nuclear weapons design. He and the Academy’s science institutions provided the theoretical basis for space exploration, rocket design, mission design and navigation in space. Unlike in the US, the Soviet Academy of Sciences was charged with developing the mathematical and scientific tools, including instruments, for space exploration, and as head of the Academy Keldysh was a major force in the development of lunar and planetary exploration in the USSR. The government often had the Academy assess the merits of projects proposed by the various design bureaus. Also, the government presented Keldysh to the international community as the face of the Soviet space exploration program, representing it abroad and to the media. His prominence went hand in glove with Korolev’s obscurity.

The Ye-4 impactor and Ye-5 orbiter designs were made obsolete by the Ye-6. It was a modular spacecraft with a carrier spacecraft on which could be mounted either a soft lander or an orbiter module. The first Ye-6 series were built at OKB-1 for soft landings on the Moon but managed not a single success after eleven straight launch attempts over three years between January 1963 and December 1965.

Luna Ye-6M (Lavochkin) series, 1966-1968

Responsibility for robotic lunar and planetary spacecraft design and construction was transferred from OKB-1 to NPO-Lavochkin in 1965. Lavochkin introduced its own modifications, and was immediately rewarded with Luna 9, which became the first successful lunar lander on February 3, 1966. Lavochkin also produced several orbiter versions, and over the following 14 months achieved a record of six mission successes out of nine Ye-6M launches. Both Ye-6M landers were successful, Luna 9 and Luna 13. After one failed launch the first model of the Ye-6S yielded the first lunar orbiter, Luna 10, which had instruments to measure the particles and fields in the lunar environment. It was then modified to acquire orbital photography. Both of these Yc-6LF missions, Luna 11 and Luna 12, were successful although no useful imagery was acquired in the first case. Finally, after another modification produced the Ye-6LS, two failed launches were followed by the Luna 14 orbiter.

Campaign objectives:

і’he first ever Venus campaign consisted of two spacecraft, each almost identical to the two lost in the failed Mars launches four months earlier. As had been the case for the Mars spacecraft, the Venus spacecraft w;ere also built in a great hurry. Although there was additional time, the schedule did not provide the iterative design process and extensive ground testing employed by later flight programs. Korolev’s engineers had to spend considerable time and effort debugging the systems. There were many disassemble, reassemble and test cycles to fix failed items, and after one fix another failure would occur. Once again the communications system was a major problem. Design issues emerged and workarounds had to be devised.

The IV Venus spacecraft had originally been intended to be a lander w ith camera, but by the time the Mars spacecraft were launched in October 1960 it had become clear that the lander w ould not be ready for the Venus launch window^ that opened in January, and the payload mass had to be significantly reduced to accommodate the instrumentation for the new launcher. The lander was abandoned and the mission

1VA No. l [Sputnik 7]

Venus Impaclor USSR /ОКВ-1 Molniya

February 4, 1961 at 01:18:04 UT (Baikonur) Failed to depart Earth orbit, fourth stage failure.

Venera 1 (1VA Ко.2)

Venus Impaclor USSR OKB-1 Molniya

February 12, 1961 at 00:34:37 UT (Baikonur) February 17, 1961 May 20, 1961

Failed in transit, communicalions lost.

descoped to a simple impactor. The goal was changed to undertaking science during the interplanetary cruise and in the environment of Venus prior to impact. Л small passive entry capsule was carried containing medallions. The 1VA redesign used as much of the 1M spacecraft as possible. Launched in February 1961, these were the second set of spacecraft to be launched to a planet, and the first to Venus, preceding the first US attempt at Venus by 18 months.

Only one 1VA spacecraft, Venera 1, was successfully launched on a trajectory to Venus. It was the first spacecraft ever successfully sent on a trajectory to another planet. Unfortunately it suffered from severe attitude control and thermal problems, and was lost after less than a week’s flight time.

The truncated flight of Venera 1 was offset by the triumph of the orbital flight by Yuri Gagarin on April 12, 1961. These achievements, together with the capability to launch heavy satellites and three successful Luna missions in 1959, established the USSR as pre-eminent in space flight in mid-1961. All that America could claim was eight lunar mission launch failures and one launch which, due to insufficient boost, resulted in a distant lunar flyby, all involving tiny spacecraft that had been created more as an afterthought to rocket development than as deliberate designs for space exploration.

Spacecraft:

The spacecraft were 2.035 meter long canisters. 1.05 meters in diameter, that were pressurized to 1.2 bar. They had 1 square meter solar arrays, medium-gain antennas on each panel, a boom omnidirectional antenna, and a dome-shaped propulsion unit on top. The sequencer, communications, attitude control, navigation, and propulsion systems w ere the same as the 1M spacecraft. The attitude control system had three modes of operations: a З-axis cruise mode for continuous solar pointing, a

back-up system for spinning about the solar axis in the event of some failure in the primary system, and a З-axis Earth pointing system for communication using the 2.33 meter high-gain parabolic mesh antenna. Thermal control was by passive louvers activated by internal temperature. A key difference with the Mars spacecraft was the addition of an Earth sensor, instead of a radio beacon, for more precise orientation during a high gain telemetry session.

The spherical entry device was mounted inside the pressurized canister, and not separable. Having been encased with thermal shielding, it was expected to survive as the rest of the spacecraft burned up on atmospheric entry. It was to free-fall through the atmosphere and impact the surface. Although it was not designed to survive an impact with a solid surface, it was expected to be able to float if it happened to come down on an ocean.

At that time the Venus ephemeris was more poorly known than Mars, the errors being about 15 times its radius, so achieving an impact was not an easy task. Radar ranging of Venus wus obtained for the first time in early April, while the planet was at inferior conjunction, enabling the ephemeris error to be reduced to 500 km. It is possible that if Venera 1 was still functioning, the Soviets would have used this new data to program a trajectory correction maneuver a few weeks prior to its arrival at the planet in May.

Launch mass: 643.5 kg

Payload:

Main spacecraft:

1. Boom-mounted triaxial fluxgate magnetometer to search for a Venus magnetic field

2. Ton trap charged particle detectors to investigate the interplanetary medium

3. Micro meteoroid detector to investigate interplanetary spacecraft hazards

4. Cosmic ray detectors to measure radiation hazards in space

5. Infrared radiometer for Venus temperature

These instruments were identical to those on the 1M Mars spacecraft. It is also reported to have had a pair of parallel magnetometers to measure the interplanetary magnetic field.

Entry probe:

1. Commemorative globe and medallion

The entry probe contained a 70 mm diameter metal globe with a commemorative medallion inside. The terrestrial oceans on the globe were blue-tinted and continents gold-tinted. It was designed to float. The medallion disk was inside the globe, which in turn was contained in a shell composed of pentagonal stainless steel elements on each of which was inscribed (in Russian) ‘Earth-Venus 196Г.

Mission description:

On February 4,1961, the new Molniya planetary rocket managed for the first time to deliver its fourth stage with attached spacecraft into a low ‘parking’ orbit. After 60 minutes of unpowered coast, the engine failed to rcignite, stranding the 1VA No. l spacecraft. The failure was caused by a power supply that used a transformer which not been designed to work in vacuum! The large orbital mass, 6,483 kg including the propulsive stage, prompted speculation in the West that it was a failed manned craft. The Soviets later said that they had been testing an orbiting platform from which an interplanetary probe could be launched. In fact, the ‘platform’ was no more than the new fourth stage of the launcher with the spacecraft attached. The Soviet description was doubtless highlighting the introduction of the parking orbit technique for deep space missions. It was designated Sputnik 7 in the US. On February 26 it re-entered the atmosphere over Siberia. Interestingly, the wreckage was discovered by a young boy and the heat-damaged pennant handed over to the KGB. The recovered articles were returned to the Academy of Sciences, which later sold them at auction in New York in 1996 to raise money for Russia’s impoverished science programs.

The powder supply problem in the first launch was traced to improperly mounting a transformer outside where it would be exposed to vacuum. A quick fix was rigged in time for the second launch by scaling the apparatus inside a vacuum-tight battery box.

On February 12. 1961. an Automatic Interplanetary Station’ that was later named Venera 1 was successfully boosted out of parking orbit. Communications sessions 2 hours and 9 hours after launch confirmed that the spacecraft was on a 96- day type I trajectory that would take it to the vieinity of Venus. Subsequent traeking indicated that a large midcourse correction would be required, but the target was in the cross-hairs! Analysis of the telemetry showed that operation in the Sun-pointing mode was unstable. The spaeeeraft automatically switched to the backup spin – stabilized mode in which most electrical systems except the sequencer and thermal control were shut down. This was a serious design error, since the command receiver was also turned off and denied the ground control of the spacecraft. In this safe mode, the spacecraft would re-activate the communication system every 5 days for a session with Earth. The high gain antenna could not be used because the spaeeeraft could not point at Earth. After an agonizing 5 days, the spacecraft contacted Earth on February 17 at a distance of 1.9 million km. The session was used to check the primary Sun-pointing operation, which failed again. On February 22 the spacecraft failed to respond, and no signal was received. The Soviets asked Jodrell Bank to listen for telemetry, and sent a team to England to assist, but nothing was heard. Attempts by Yevpatoria on March 4 and 5 also failed to receive any signal. Due to the inability to conduct a midcourse maneuver. Venera 1 flew silently past the planet at 100,000 km distance. In case it was silently continuing its mission, commands were sent on May 20. 1961. the day of the encounter, without result.

It was later determined that the altitude control system failure was due to the Sun sensor overheating. The thermal control design had only considered the average temperature for the instrument, and not the localized temperature at an unpressuri/ed sensitive clement. The lack of response after February 17 was attributed to a failure of the sequencer for the communications system. There was also evidence that the motorized thermal control shutters were not operating properly.

The flight of Venera 1 was followed worldwide as the first mission to another planet – another coup for the Soviet Union. But failure followed quickly. Radio Moscow announced the loss on March 2, noting that an investigation was underway and that sabotage was not excluded. The window closed on February 1 5, before the third 1VA could be launched.

Results:

None for Venus. Results were obtained from the Venera 1 instruments during its short cruise period. A faint interplanetary magnetic field on the order of 3.5 nT was reported and the solar wind plasma flow discovered by Luna 1 to 3 was found to be present beyond the Earth’s magnetopause in deep space. Venera 1 marked the first flight of a true interplanetary spacecraft with all the capabilities necessary for such a mission, including flexible attitude stabilization modes and midcourse maneuvering.

Campaign objectives:

The Ye-8 series was developed to support the Soviet lunar cosmonaut program. By the time that the Soviets entered the Moon race in mid-1964 Russian engineers at OKB-1 had already developed plans for a lunar rover. This, along with all the other lunar robotic programs, was transferred to NPO-Lavoehkin in 1965. In early 1966 an automated lunar surface rover entered the mission plan for supporting a cosmonaut on the lunar surface. The function of the rover was to precede the cosmonaut to the landing site, to survey and certify the site as safe for landing, to act as a radio beacon to guide the manned lander in, to inspect this lander after touchdown and certify it as safe for ascent, and, if it were not so, to transport the cosmonaut to a backup ascent vehicle that was already in place.

When the robotic lunar exploration program was transferred to NPO-Lavoehkin. Georgi Babakin set to work on a design for a spacecraft to meet these requirements. The availability of the powerful four-stage Proton launch vehicle using the Block D translunar injection stage enabled the resulting Ye-8 to be much heavier and more complex than its Ye-6 predecessor. The multi-purpose, in-line module design of the Ye-6 series was abandoned for a spacecraft design suited principally for soft landing a rover, and eventually other types of payload.

Spacecraft:

The spacecraft comprised three main components; a lander stage on the bottom, the rover that was carried on top, and a pair of side-mounted backpacks’, each of which had avionics and two cylindrical propellant tanks.

Cruise and lander stages:

The lander stage was based on a quartet of 88 an diameter spherical propellant tanks arranged in a square 4 meters on a side and connected using cylindrical inter-tank sections. These tanks fed a single engine whose thrust could be varied over the range 7.4 to 18.8 kN and a set of six vernier engines, two of which were mounted next to the main engine and were for use during the final descent to the surface. The other verniers were positioned around the periphery to provide stabilization. The landing system, engine, and radar altimeter were located between the tanks on the underside of the square tank assembly. Hach of the tanks supported a shock absorbing landing leg. Attitude control thrusters were located at various places around the lander. The avionics and attitude control sensors to control the translunar trajectory, lunar orbit insertion, orbital maneuvers, and landing, were housed in the inter-tank cylindrical sections. Water cooling was used for thermal control. Communications at 922 MHz and 768 MHz were by way of a cone-shaped antenna mounted on a boom. Uplink was at 115 MHz.

The two detachable backpacks’ were mounted vertically on opposite sides of the square tank assembly and were for cruise and orbital operations, bach consisted of a pair of 88 cm diameter cylindrical tanks, between which were avionics and battery modules. The tanks contained propellants to feed the main engine. On top of each of these tanks was a smaller spherical tank of nitrogen for the cold gas attitude control system.

The Isayev design bureau built the new throttleable KTDIJ-417 main engine. Its purpose was to conduct midcourse maneuvers during the translunar coast, lunar orbit insertion, orbital maneuvers, and key portions of the descent. Once the operational orbit at about 100 km altitude had been achieved, descent to the surface began with a burn of about 20 m/s to lower the perilune to about 15 km directly over the landing site. The backpacks were jettisoned and. with perilune looming, the main engine was ignited for a 1.700 m s ‘dead stop’ burn lasting 270 seconds designed to completely eliminate its horizontal velocity. After the spacecraft had free fallen to an altitude of about 600 meters and accelerated in the weak lunar gravity to a descent rate of about 250 m/s the main engine was reignited. This was shut down at 20 meters and the landing verniers ignited until a contact switch cut them off at a height of 2 meters. If all had gone to plan, the vehicle would then touch down at a velocity not exceeding 2.5 m/s. Unlike the Ye-6 soft landers, whose targets were constrained by the need to make a vertical descent from the translunar coast, the new spacecraft, by first going into orbit, could land anywhere.

f or a rover mission, two sets of folding ramps were mounted on top of the upper side of the lander fore and aft of the rover, whose wheels were on the middle of the ramps. The ends of the ramps were carried folded up against the rover, and once on the Moon they were unfolded and lowered to provide the rover with two options for driving off the lander down onto the surface.

Lunokhod rover:

The body of the Lunokhod rover was a tub-like pressurized magnesium alloy shell for avionics, instruments and environmental controls covered by a large hinged lid. In daylight on the lunar surface the convex lid would be opened over the rear of the rover to expose solar cells on the inside surface of the lid to generate pow er and also to expose radiators in the top of the ‘tub’ for thermal control. In darkness the lid was closed. It was a very simple and effective design. The solar cells (Si on Lunokhod 1 and GaAs on Lunokhod 2) gave 1 kW of power to recharge the internal batteries. The body was mounted on a carriage of eight wheels, 51 cm in diameter and made of ware mesh with titanium blade treads. This design was in response to the data on lunar soil provided by Luna 9; the thin dust layer and firm soil that this found led to the abandonment of a caterpillar track design. Each wheel had its own suspension system using a special fluoride based lubricant to operate in vacuum, a pressurized independent DC motor and an independent brake.

The rover was controlled entirely from Earth by a five-person team, there was no automated mode, and steering required independently changing the speed settings on the wheels. It could move with only two operational wheels on each side, and any of

the axles could be severed to shed a wheel if it became locked. The smallest turning radius was 80 cm. Internal gyroscopes indicated its orientation. It was designed to drive over obstacles 40 cm high or 60 cm wide, to climb slopes of 20 degrees, and to maneuver on slopes as steep as 45 degrees. There were fail-safe devices to prevent movement over excessive slopes. Lunokhod 1 had only one driving speed, 800 m/hr, traveling either forward or in reverse, but Lunokhod 2 was capable of 800 and 2,000 m/hr in either direction.

The control team operated and navigated the vehicle by viewing through a pair of television cameras mounted on the front of the rover. These returned low resolution images at a rate of 20 seconds/frame for Lunokhod 1 and at the much improved rate of up to 3.2 seconds/frame for Lunokhod 2. The signal time delay to the Moon and back to Earth was 5 seconds, which had an effect on operations. Pour other scanning photometer imagers of the type used on Luna 9 were mounted on the chassis. A pod on each side held a vertically mounted imager to give a 180 degree view at a 15 degree down angle, jointly providing a full panoramic view around the rover. A second imager was set above the first, nearer the top of the ‘tub’, and was mounted horizontally. These would jointly provide a full vertical panorama that included the sky and stars for navigation at the zenith and a vehicle level indicator at the nadir.

The rover was designed to survive three lunar nights, each lasting a fortnight over a period of 3 months. In darkness it was the kept alive by a small radioisotope heater with 11 kg of polonium-210 and by a radiator on top of the closed lid. Thermal control was by circulating internal air and by open-cycle water cooling. The rover was equipped with a conical low gain antenna, a steerable directional helical high gain antenna, television cameras, and extendable devices to impact the surface for soil density and mechanical property tests. Lunokhod 1 was 135 cm high, 170 cm long, 215 cm wide at the top, 160 cm wide at the wheels, had a wheelbase of 2.22 x

1.6 meters, and a mass of 756 kg.

Lunokhod 2 was an improvement based on experience with Lunokhod L It had an additional camera on the front at adult height for easier navigation. Its images could be transmitted at rates of 3.2, 5.7, 10.9 or 21.1 seconds‘frame, with the fastest rate being instrumental in improving driving operations. The 8-wiiecl drive system was improved, and Lunokhod 2 was twice as fast for twice the range. Additional science instruments were carried.

Luna 17 launch mass: 5,660 kg (landed mass 1,900 kg; rover 756 kg)

Luna 21 launch mass: 5,700 kg (landed mass 1,836 kg; rover 836 kg)

Payload:

Lunokhod 1:

1. Two television cameras for stereo images in the direction of travel

2. Four panoramic imagers

3. PrOP odometer/speedometer and soil mechanics penetrometer

4. Soil x-ray fluorescence spectrometer

5. Cosmic ray detectors

6. X-ray telescope for solar and extragalactic observations

7. Laser retro-reflector (France)

8.

Radiometer

four imagers were facsimile cameras of the type flown on Luna 9, with improved sensitivity and gain control and mounted two to a side. One camera in each pair was mounted for 180 degree horizontal scanning and the other for vertical scanning from surface to sky. bach 180 degree panorama consisted of 500 x 3,000 pixels. Between them, each pair of cameras provided a 360 degree panorama. The horizontal ones provided context for the forward cameras and the vertical ones assisted navigation in the driving process.

A ninth spiked wheel trailed behind the rover with an odometer to measure distance and speed. The surface penetrometer was mounted on a pantograph. The French laser retro-reflector weighed 3.5 kg and consisted of fourteen 10 cm silica glass prisms. It was designed for 25 cm accuracy. Due to Soviet secrecy, the French were given only a drawing for how the device would be mounted and were not told in advance what kind of lunar vehicle would carry it.

Lunokhod 2:

1. Three front television cameras for stereo images in the direction of travel

2. Four panoramic imagers

3. PrOF odometer/speedometer and soil mechanics penetrometer

4. Soil x-ray fluorescence spectrometer (Rifma-M)

5. Cosmic ray detectors

6. X-ray telescope for solar and extragalactic observations

7. Laser retro-reflector (France)

8. Radiometer

9. Visible-ultraviolet photometer

10. Boom magnetometer

Based on experience with Lunokhod 1, a third forward viewing television camera was mounted higher on Lunokhod 2 to provide a better driving perspective while the lower pair of television cameras provided stereo images of potential obstacles. The visible-ultraviolet photometer was to detect Larth airglow and galactic ultraviolet sources. The magnetometer was mounted on a 1.5 meter long boom in front of the rover. A Soviet-made photocell was added to the French retro-reflector to register laser strikes and the x-ray fluorescence spectrometer was improved.

Mission description:

First attempt falls do war aitge

The first attempt to launch a Ye-8 with a rover failed spectacularly on February 19. 1969, when the payload stack on top of the vehicle disintegrated 51 seconds into the flight. The launcher then exploded and scattered wreckage 15 miles downrange. The investigation discovered that at the point of maximum dynamic pressure, when the loads on the vehicle were greatest, the newly designed payload shroud for the Proton failed. The radioisotope heater that was to have kept the rover warm during the lunar night was never recovered from the debris, and rumors persist that the soldiers who actually found it decided to use it to heat their barracks during that year’s very cold winter.

Luna 17

A second attempt to launch a lunar rover was not made until 20 months later. After the loss of the first mission, the Ye-8 program had focused on attempts at automated lunar sample return in an effort to upstage Apollo. After Luna 16 succeeded with a returned sample in October 1970 it was decided, to launch a rover next. The back to back successes of an automated sample return mission and. a rover one month apart were impressive milestone achievements for the Soviet robotic lunar program.

Luna 17 was launched on November 10, 1970. After midcourse corrections on the 12th and 14th, it entered an 85 x 141 km lunar orbit on the 15th inclined at 141 degrees with a period of 115 minutes. It lowered its perilune to 19 km on the 16th and then at 03:46:50 UT on the 17th successfully touched down at a speed of about 2 m/s in the Sea of Rains at 38.25°N 325.00°E.

The Soviets announced their fourth lunar soft landing, and Westerners expected another sample return like Luna 16. However, about 3 hours after landing, at 06:28 UT, the ramps were lowered, the camera covers released, pictures of the ends of the

ramps were taken to ensure that there were no obstructions, and Lunokhod 1 rolled down the front ramp and 20 meters across the surface. The next day it remained in place and recharged its batteries, then it traveled 90 and 100 meters on the next two days. On the fifth day, 197 meters from its lander, it closed its lid and shut down for the forthcoming lunar night.

The public reaction across the world was astonishing. Somehow, people resonated strongly with the idea of a robotic rover driving around on another world, even if the experience was only a virtual one. The Luna 17 rover was a triumph heralded by the Soviet and Western press alike, whereas the Luna 16 sample return had only gained fleeting admiration. The appeal of the Lunokhod may have been partly derived from its physical form. Its antics were followed ardently in the press for the first few’ days, and the coverage would probably have continued were it not for the requirement to

shut it down for the long lunar night. It would be more than a quarter of a century before the US would recreate the excitement of a robotic rover on another world.

Lunokhod 1 survived its first lunar night and continued its activities. The drivers had some difficulty coming to terms with the frame rate of 20 seconds, and it was realized that the driving cameras had been set too low on the vehicle because their perspective was more like sitting on a chair than standing upright. And their images were so overexposed that the contrast in the scene was poor, especially near lunar noon. Initially excluded from the control room, the scientists had difficulty m having the rover pause at interesting rocks. This was because the engineers’ measure of success was distance covered. However, as the mission wore on it became easier for the scientists to achieve their objectives.

The operators drove the rover over 197 meters on the first lunar day, and as far as 2 km on the fifth lunar day. To test its navigational system, on one early excursion it returned to the lander stage. Over a period of 10 months it traversed rough hills and valleys and crossed many craters. It survived the -150°C cold of the lunar night and 100 C heat of lunar noon. It twice became stuck in craters, but after some effort was able to extract itself. The drivers had difficulty navigating because of the low mount of the cameras which meant they often did not spot a crater until the last moment. At noon the lack of shadows reduced the contrast to /его, making steering impossible. The rover survived a solar flare that might have been fatal for cosmonauts and an eclipse during which it was temporarily plunged into darkness. On the tenth lunar day it was spotted from orbit by the Apollo 15 astronauts.

The last successful communications session with Lunokhod 1 ended at 13:05 UT on September 14. 1971, after the internal pressure suddenly dropped. Officially, the mission concluded on October 4, 1971, the 14th anniversary of Sputnik. Fortunately, during its last communication cycle it had been parked with the laser retro-reflector in a position where it could continue to be used. Lunokhod 1 exceeded its expected lifetime of three lunar days by functioning for eleven lunar days. It traveled a total of 10,540 meters and transmitted more than 20.000 individual pietures, 206 panoramas. 25 x-ray elemental soil analyses, and more than 500 soil penetrometer tests. It was a spectacular success.

Luna 21

The next rover was modified to take account of the lessons from Lunokhod 1. and on January 8, 1973. Luna 21 was launched carrying Lunokhod 2. It performed a midcourse maneuver the next day, and on January 12 entered a 90 x 110 km lunar orbit inclined at 62 degrees with a period of 118 minutes. It lowered its perilune to 16 km the following day and then on January 15 fired its main engine at perilune to de­orbit itself. At an altitude of 750 meters the main engine ignited again to slow7 the rate of descent. At 22 meters this engine was shut down. The verniers took over to a height of 1.5 meters and were cut off. After falling the remaining distance the 7 m/s shock was absorbed by the legs. Luna 21 landed at 23:35 IJT at 26.92 N 30.45 E in Le Monnier bay. an eroded and lava flooded crater cut into the Taurus Mountains on the eastern shore of the Sea of Serenity.

The Lunokhod 2 rover immediately took TV images of the surrounding area from its perch atop the lander. After rolling down onto the surface at 01:14 UT on January 16 it took pictures of the lander and the landing site. It remained in place for 2 days until its batteries were charged, then took some more pictures and began its traverse. During its first full lunar day it covered a greater distance than its predecessor had in eleven lunar days. In one day. it traveled as much as 1.148 meters. It climbed a hill 400 meters high and photographed the peaks of the Taurus mountains poking over the horizon with Earth in the sky above. In late January 1973 an American scientist attending an international conference on planetary exploration in Moscow^ gave a set of Apollo 17 photos of the area w’here Luna 21 landed to Russian scientists at the meeting. These highly detailed photographs were used to navigate Lunokhod 2 to a rille some distance east of its landing site.

Rover operations were conducted during the lunar day, stopping occasionally to recharge the battery using its solar panels. It would hibernate during the lunar night, using the radioisotope heater to maintain thermal control.

Lunokhod 2 operated lor about 4 months, drove 37 km over terrain including hilly upland areas and rilles, more than four times the area of its predecessor, and returned over 80,000 individual images and 86 panoramas. It made hundreds of elemental analyses and mechanical tests of the soil, as well as being used for laser

ranging and other experiments. On May 9, 1973, it accidentally rolled into a small 5 meter crater whose depth had been concealed by a shadow. As the rover was backing itself out, it scraped its lid on the crater wall, causing a spray of dust to cover the solar panel. When the lid was closed for the lunar night, this soil was dumped onto the radiators. On opening the lid for the next lunar day, the resulting thermal and power problems led to the vehicle’s demise, which was announced on June 3.

Results:

Significant scientific results derived from analyzing the pictures of rocks and soil, wheel tracks, craters and other geological features observed by the twjo Lunokhods in more than 20,000 single frame images and 200 panoramas. There were many soil mechanics measurements by the penetrometer and chemical analysis results from the x-ray fluorescence spectrometer. The Sea of Rains and floor of Le Monnier proved to be a typical mare basalt, but the uplands around Le Monnier (the surviving part of the rim of the eroded crater) turned out to have higher concentrations of iron, silicon, aluminum and potassium.

Lasers fired by the French from the Pic du Midi observatory and by the Russians from the Semeis observatory in the Crimea used the retro-reflectors to determine the distance to the Moon to within 3 meters for Lunokhod 1, and 40 cm for Lunokhod 2. In the long term, such observations established the periodic and secular dynamics of the Moon. The cosmic ray instruments recorded the radiation on the Moon, and the x – ray telescope observed the Sun and the galaxy. The magnetometer on Lunokhod 2 measured a very weak magnetic field with variations due to currents induced by the interplanetary magnetic field. The photometer made some surprising observations of the brightness of the lunar sky. In particular, it determined that the day-time lunar sky was contaminated with some dust, and in Earthlight the night-time lunar sky was 15 times brighter than the sky on Earth at full Moon; findings which did not bode well for one day establishing astronomical observatories on the lunar surface.

TIMELINE: 1974-1976

Afler abandoning its manned lunar program, the USSR continued to send robotic missions. In May 1974 they launched Luna 22, which became their second orbiter in the new heavy series. The Luna 23 sample return mission in October 1974 damaged its drill system on landing, which ruined the mission. A year later, another sample return mission was lost to a Block D failure. But Luna 24 launched in August 1976 became the third successful sample return. This drew to a conclusion the long line of missions which began with Luna 1 to 3, small 300 kg spacecraft that used the three-stage R-7 Luna launcher, then Luna 4 to 14, with 1,600 kg spacecraft that used the four-stage R-7 Molniya, and finished with Luna 15 to 24, with 5,800 kg spacecraft that used the four-stage Proton-K. There had been many failures but this series gave the Soviets the first lunar flyby, first lunar impact, first pictures of the far side of the Moon, first landing, first orbiter, first sample return, and first surface rover.

After the objectives of the direct-entry 3MV series at Venus were achieved by the landing of Venera 8 in 1972, the Soviets stood down during the 1973 opportunity in order to develop a spacecraft capable of both orbiting the planet and dispatching a larger and more capable lander equipped with imagers. They based the new Venera on the Proton-launched Mars spacecraft that proved itself in 1971. In June 1975 two were launched as Venera 9 and 10. They both performed spectacularly by releasing their entry systems inbound and then entering orbit around the planet. Furthermore, both landers yielded atmospheric data and survived on the surface for about an hour, from where they took the very first black-and-white pictures from the surface of the planet and returned data on the composition of the rocks.

W. T. Huntress and M. Y. Marov, Soviet Robots in the Solar System: Mission Technologies and Discoveries, Springer Praxis Hooks 1, DOl 10.1007/978-1-4419-7898-1 14,

© Springer Science+Business Media, LLC 2011

The US sent its two sophisticated Viking spacecraft to Mars in 1975. Both were highly successful, the orbiters as well as the landers. Reeling front the failure of their all-out assault on Mars in 1973 and the awesome performance of the Vikings, the Soviets abandoned their long and hapless campaign at Mars in favor of Venus. They would not develop the confidence to resume Mars missions until 1988. Meanwhile, their new Venera spacecraft delivered a long string of successes.

Russian spacecraft were given “tail numbers” during construction. Luna spacecraft were given the designation Ye followed by a number indicating the design senes and a second number indicating the serial number of the particular spacecraft under construction, 1 e. Ye-3 No.2 was the second spacecraft built in the third design series of lunar spacecraft. Sometimes a letter was attached to indicate a modification to the original design, such Ye-2A No. l. After successful translunar injection, the spacecraft were renamed “Luna”.

The designation scheme for planetary spacecraft was somewhat different. The early 1960-1961 spacecraft were simply designated 1M or IV for the first design series of Mars or Venus spacecraft. The next generation were a common design for both Mars and Venus and were designated as follows:

Example: 3MV-1 No.3

First number: Serial number of design (3rd major design series)

Second set of letters: Spacecraft targets (MV = Mars, Venus common design)

Third number: Mission modification number:

1 — Venus Entry Mission

2 – Venus Flyby Mission

3 – Mars Entry Mission

4 – Mars Flyby Mission

Fourth number: Serial number of vehicle (No.3, or third to be built)

The spacecraft were renamed after successful departure from earth orbit as “Venera” (for Venus) or “Mars” spacecraft.

A few 3MV planetary spacecraft were built for engineering test flights and were given “ІА” designations including a failed Mars test flight 3MV-1A No.2 on Nov 11, 1963, and a failed Venus test flight 3MV-1A No.4A on Feb 19, 1У64. Oddly, the Zond 3 Mars spacecraft, 3MV-4 No.3, wras not given a “1A” designation, but carried out a successful flyby test at the Moon before failing to reach Mars distance.

Three 3MV Mars spacecraft, one entry probe (3MV-3 No. l) and two flyby spacecraft (3MV-4 No.4 and No.6) that missed their launch window in 1964 were modified as Venus spacecraft and launched in 1965. Their original construction as Mars missions accounts for their anomalous tail numbers.

There is confusion in the literature over the tail numbers assigned by OKB-1 to the early Luna, Venera and Mars spacecraft before Lavochkin assumed responsibility. The most authoritative original source for Mars and Venus spacecraft is Chertok. The most authoritative secondary source for all spacecraft is Siddiqi’s Deep Space Chronicle. There remain some inconsistencies between these and other sources in the literature. We have attempted to reconcile all these sources to the extent possible through communications with both Asif Siddiqi and Timothy Vatfolomeyev, and on this basis have chosen to use the tail number designations given in Chertok.

W. T. Huntress and M. Y. Marov, Soviet Robots in the Solar System: Mission Technologies and Discoveries, Springer Praxis Hooks 1, DOl 10.1007/978-1-4419-7898-1,

.© Springer Scienee+Bustness Media, LLC 2011

Launch date T,/v Mass (kg) Builder Spacecraft Mission name Mission type Result Luna Soviet Lunar Missions Ye-1 series (OKB-l) Sep 23, 1958 Tama -360 OKB-l Ye-1 No. l Tamar Tmpaclor fb Oct 11, 1958 Luna ~ 560 OKB-l Ye-1 No.2 Lunar Impact or fb Dec 4, 1958 Luna -360 OKB-l Yc-1 N o. 3 Lunar Impact or fb Jan 2, 1959 Luna 361.3 OKB-l Ye-1 no. 4 Luna 1 Lunar Impact or ft Jim 18. 1959 Luna — 390 OKB-l Ye-1 A No.5 Lunar Impact or fb Sep 12, 1959 Tama 390.2 OKB-l Ye-1 A No.7 T. una 2 Tamar Tmpaclor s Ye-2,3 series (OKB-l) Oct 4. 1959 Luna 278.5 OKB-l Ye-2A No. l Luna 3 Oircumlunar Flyby s Apr 15, 1960 Tama 9 OKB-l Ye-3 No. l Oirc uni lunar Flyby flL Apr 19, 1960 Tama 9 OKB-l Ye-3 No.2 Oircumlunar Flyby fb Yc-6 Scries (OKB-l) Jan 4, 1963 Molniya 1.420 OKB-l Ye-6 No.2 [Sputnik 25J Lunar Lander fi Feb 3, 1963 Molniya 1.420 OKB-l Ye-6 No.3 Tamar Lander fb Apr 2, 1963 Molniya 1,422 OKB-l Yc-6 No.4 Luna 4 Lunar Lander fe Mar 21, 1964 Molniya-M -1,420 OKB-l Yc-6 No.6 Lunar Lander fu Apr 20, 1964 Molniya-M — 1.420 OKB-l Ye-6 No.5 Lunar Lander fu Mar 12, 1965 Molniya – 1.470 OKB-l Ye-6 No.9 Cosmos 60 Lunar Lander fi Apr 10, 1965 Molniya ~ 1,470 OKB-l Ye-6 No.8 Lunar Lander fu May 9. 1965 Molniya-M 1.476 OKB-l Ye-6 No. 10 Tama 5 Tamar Lander ft Jun 8, 1965 Molniya-M 1,442 OKB-l Yc-6 No.7 Luna 6 Lunar Lander le­ Ocl 4, 1965 Molniya 1,506 OKB-l Yc-6 No. 11 Luna 7 Lunar Lander ft Dec 3, 1965 Molniya 1,552 OKB-l Yc-6 No. 12 Luna 8 Lunar Lander ft

Jan 31. 1966 Molniya-M 1,538 NPO-L Ye-6M No.202/13 Luna 9 Lunar Lander s Mar 1, 1966 Molniya-M ~ 1.580 NPO-L Ye-6S No.204 Cosmos 111 Lunar Or biter fi Mar 31. 1966 Molniya-M 1.582 NPO-L Ye-6S No.206 Luna 10 Lunar Orbiler •S Aug 24, 1966 Molniya-M 1,640 NPO-L Yc-6LF No.101 Luna 11 Lunar Orbiler s Ocl 22, 1966 Molniya-M 1,620 NPO-L Yc-6LF No. 102 Luna 12 Lunar Orbiler s Dec 21. 1966 Molniya-M 1,620 NPO-L Ye-6M No.205/14 Luna 13 Lunar Lander s May 16, 1967 Molniya-M -1.700 NPO-L Ye-6LS No. Ill Cosmos 159 Lunar Or biter Test Flight til Feb 7, 1968 Molniya-M -1.700 NPO-L Ye-6LS No. 112 Lunar Or biter til Apr 7, 1968 Molniya-M 1.700 NPO-L Ye-6T. S No. 113 Luna 14 Lunar Orbiler •S Yc-8 scries (NPO-L) Feb 19. 1969 Proton-D -5.700 NPO-L Ye-8 No.201 Lunar Lander/Rover fll Jun 14, 1969 Prolon-D -5.700 NPO-L Ye-8-5 No. 402 Lunar Sample Return fu Jul 13, 1969 Prolon-D 5.667 NPO-L Ye-8-5 No. 401 Luna 15 Lunar Sample Return ft Sop 23, 1969 Prolon-D – 5,700 NPO-L Yc-8-5 No.403 Cosmos 300 Lunar Sample Return til Ocl 22, 1969 Prolon-D – 5,700 NPO-L Ye-8-5 No.404 Cosmos 305 Lunar Sample Return ill Feb 6, 1970 Proton-D -5,700 NPO-L Ye-8-5 No.405 Lunar Sample Return fll Sep 12. 1970 Proton-D 5.727 NPO-L Ye-8-5 No.406 Luna 16 Lunar Sample Return s Nov 10. 1970 Prolon-D 5.660 NPO-L Ye-8 No.203 Luna 17 Lunar Lander/Rover •S Sep 2. 1971 Prolon-D 5.750 NPO-L Ye-8-5 No, 407 Luna 18 Lunar Sample Return ft Sep 28, 1971 Prolon-D 5,700 NPO-L Yc-8LS No.202 Luna 19 Lunar Orbiler s Fob 14, 1972 Prolon-D 5,750 NPO-L Yc-8-5 No.408 Luna 20 Lunar Sample Return s Jan 8, 1973 Proton-D 5.700 NPO-L Ye-8 No.204 Luna 21 I. u nar I. ander/ R over s May 29, 1974 Proton-D 5,700 NPO-L Ye-8LS No.206 Luna 22 Lunar Or biter s Ocl 28, 1974 Prolon-D 5.795 NPO-L Ye-8-5M No.410 Luna 23 Lunar Sample Return ft Ocl 16, 1975 Prolon-D -5.800 NPO-L Ye-8-5M No.412 Lunar Sample Return fu Aug 9. 1976 Prolon-D 1 5.795 NPO-L Ye-8-5M No.413 Luna 24 Lunar Sample Return s Zond Soviet lunar test missions Sep 27, 1967 Prolon-D -5.375 TsKBF. M 7K-T.1 No.4T. Oirc uni 1 unar/R el urn fb Nov 22. 1967 Prolon-D -5.375 TsKBF. M 7K-T.1 No.5L Circimilu nar/Ret urn fll Mar 2, 1968 Prolon-D 5,375 TsKBEM 7K-L1 No.6L Zond 4 Lunar Distance;Return ft

Launch date L/V Mass (kg) Builder Spacecraft Mission name Mission type Result Apr 22, 1968 Proton-D -5,375 TsKBEM 7K-L1 No.7L Ci r cu m 1 u n ar / R ct u г n fu Sep 14, 1968 Proton-D 5,375 TsKBEM 7K-L1 No.9L Zond 5 ( A rcu ml u па r / Rot u rn s Nov 10, 1968 Proton-D 5,375 TsKBEM 7K-L1 No,12L Zond 6 Circum 1 unar / Return It Jan 20, 1969 Prolon-D -5,375 TsKBEM 7K-T.1 No. l3T, Circum 1 un ar/R et urn fu Feb 2L 1969 N-l 6,900 TsKBEM 7K-L1S No.3S Or biter./Return ib Jul 3, 1969 N-l 6,900 TsKBEM 7K-L1S No.5L Or biter./Return ib Aug 7. 1969 Prolon-D 5,375 TsKBEM 7K-L1 No. ll Zond 7 Circu mlunar/Re turn s Oct 20, 1970 Proton-D 5,375 TsKBEM 7K-L1 No.14 Zond 8 Ci reu tn 1 u nar/ Rctu rn s Nov 23, 1972 N-l 9,500 TsKBEM 7K-LOK No. fiA Orbiler/Return lb Mars Soviet Mars missions 1M series (OKB-l) Oct 10, 1960 Molniya 650 OKB-l 1M No. l Mars Flyby Ги Oct 14, 1960 Molniya 650 OKB-l 1M No.2 Mars Flyby iu 2MV combination Mars-Venus series (OKB-l) Oct 24. 1962 Molniya -900 OKB-l 2MV-4 No.3 Mars Flyby fi Nov L 1962 Molniya 893.5 OKB-l 2MV-4 No.4 Mars 1 Mars Fly by- fc Nov 4, 1962 Molniya 1,097 OKB-l 2MV-3 No. l Mar s Atm/SuiT Probe il 3MV combination Mars-Venus series (OKB-l) Nov 11,1963 Molniya -800 OKB-l 3MV-1A No.2 Cosmos 21 Test Flight П Nov 30, 1964 Molniya 950 OKB-l 3MV-4 No.2 Zond 2 Mars Flyby i’e Jul 18, 1965 Molniya 960 OKB-l 3MV-4 No.3 Zond 3 Test Flight with Lunar Flyby p NPO-L Proton series Mar 27. 1969 Proton-D 4.850 NPO-L M-69 No.521 Mars Or biter iu Apr 2, 1969 Prolon-D 4.850 NPO-L M-69 No.522 Mars Or biter ib May 10. 1971 Proton-D 4,549 NPO-L M-71 No. 170 Cosmos 419 Mars Orbitcr fi May 19. 1971 Proton-D 4,650 NPO-L M-71 No.171 Mars 2 Mars Or biter/Lander P

Launch date L/V Mass (ks) Builder Spacecraft Mission name Mission type Result Jan 10, 1969 Molniya-M 1,138 NPO-L 2V No.331 Venera 6 Venus Atm/Surf Probe s Aug 17, 1970 Molniya-M 1,180 NPO-L 3V No.630 Venera 7 Venus Atm/Surf Probe s Aug 22, 1970 Molniya-M – 1,180 NPO-L 3V No.631 Cosmos 359 Venus Atm/Surf Probe П Mar 27, 1972 Molniya-M 1,184 NPO-L 3V No.670 Venera 8 Venus Atm/Surf Probe s Mar 31, 1972 Molniya-M -1,180 NPO-L 3V No.671 Cosmos 482 Venus Atm/Surf Probe fl NPO-L Proton series Tun 8, 1975 Proton-D 4,93 6 NPO-L 4V-1 No.660 Venera 9 Venus Orbiter/ Lander s Jun R 1975 Proton-D 5,033 NPO-L 4V-1 No.661 Venera 10 Venus Orbiter/ Lander s Sep 9, 1978 Proton-D 1 4,450 NPO-L 4V-1 No.360 Venera 11 Venus Flyby/Lander s Sep 14, 1978 Proton-D 1 4,461 NPO-L 4V-1 No.361 Venera 12 Venn s FI у by /1 /and ei* s Oct 30, 1981 Proton-D 1 4,363 NPO-L 4V-1M No.760 Venera 13 Venn s FI у by /1 /and er s Nov 4, 1981 Proton-D 1 4,363 NPO-L 4V-1M No,761 Venera 14 Ven us FI у by/Izander s Tun 2, 1983 Proton-D 1 5,250 NPO-L 4V-2 No.860 Venera 15 Venus Orbiter s Jun 1, 1983 Proton-D 1 5,300 NPO-L 4V-2 No.861 Venera 16 Venus Orbiter s Dec 15, 1984 Proton-D 1 4,924 NPO-L 5VK. No.901 Vega 1 Venus Balloon & Lander Halley Flyby s s Dec 21, 1984 Proton-D 1 4,926 NPO-L 5VK No.902 Vega 2 Venus Balloon & Lander TTalley Flyby s s

1. Mass column lists mass at launch

2. Result Codes:

fh

fu

fi

ic

ft

P

booster failure upper stage failure

interplanetary trajectory injection failure failure in transit during cruise failure at the target partial success

success

4^ to

Automated tests of lunar Soyuz spacecraft Successes Post-launch failures Launch failures Zoncl 5 C і г си ml u nar; Return 1968 Zond 4 Lunar Distan ce/Return 1%8 7K-L1 No.4L Zond Circumlunar 1967 Zond 7 Circiunlunar/Rcturn 1969 Zond 6 Circumlunar/Return 1968 7K-L1 No.5L Zond Circumlunar 1967 Zoud 8 Circumlunar/Return 1970 7K-L1 No.7L Zond Circumlunar 1968 7K-L1 No. l3L Zond Circumlunar 1969 7K-L1S No.3S Zond Or hi ter/Return 1969 7K-L1S No.5L Zond Orhiter/Return 1969 7K-LOK No.6A Soyuz Orhiter/Return 1972 Dates are for launch

Dales are lor launch * test launch

Partial successes Post-launch failures Launch failures Mars 2 Orbilcr [lander failed] 1971 Mars 1 Flyby 1962 1M No. l Flyby 1960 Mars 3 Orbilcr [lander failed] 1971 Zond 2 Flyby 1964 1M No.2 Flyby 1960 Mars 5 Orbitcr [short lived] 1973 Zond З* [success at the Мост] 1965 2MV-4 No.3 Flyby (Sputnik 22) 1962 Mars 6 Flyby/Lander [descent data only] 1973 Mars 4 Or biter 1973 2MV-3 No. l Probe (Sputnik 24) 1962 Phobos 2 Orbiter/Landers [failed at Phobos] 1988 Mars 7 Fly by/lander 1973 3MV-1A No.2 Probe* (Cosmos 21) 1963 Phobos 1 Or biter/T binders 1988 M69-1 Orbiter 1969 M69-2 Orbilcr 1969 M71-S Orbitcr 1971 Mars 96 Orbitcr/Landers 1996

Successes Post-launch failures Launch failures Mariner 4 Flyby 1964 Mars Observer Orbiter 1992 Mariner 3 Flyby 1964 Mariner 6 Flyby 1969 Mars Climate Orbiter 1998 Mariner 8 Orbiter 1971 Mariner 7 Flyby 1969 Mars Polar Lander/Penetrators 1999 Mariner 9 Orbiler 1971 Viking 1 Orbi ter/T zander 1975 Viking 2 Orb iter/Lander 1975 Mars Global Surveyor Orbiler 1996 Mars Path tinder Lander 1996 Mars Odyssey Orbiter 2001 Spirit Rover 2003 Opportunity Rover 2003 Phoenix Lander 2005 Mars Reconnaissance Orbiter 2007 Dates are lor launch

Successes Pnsl-launclt failures Launch failures Venera 4 Atm/Surf Probe [lost in atm] 1967 Venera 1 Impact or 1961 1VA No. l Impact or (Sputnik 7) 1961 Venera 5 Atm/Surf Probe [imploded] 1969 Zond 1 Atm/Surf Probe 1964 2MV-1 No.3 Atm/Surf Probe (Sputnik 19) 1962 Venera 6 Atm/Surf Probe [imploded] 1969 Venera 2 Flyby 1965 2MV-1 No.4 Atm/Surf Probe (Sputnik 20) 1962 Venera 7 Aim/Surf Probe 1970 Venera 3 Alm/Surf Probe 1965 2MV-2 No. l Flyby (Sputnik 21) 1962 Venera 8 Aim/Surf Probe 1972 3MV-1A No.4A Alm/Surf Probe* 1964 Venera 9 Orbilcr/Landcr 1975 3MV-1 No.5 Alm/Surf Probe (Cosmos 27) 1964 Venera 10 Orbiter/Landcr 1975 3MV-4 No.6 Flyby (Cosmos 96) 1965 Venera 11 Flvby/Lander [imager failed] 1978 IV N0.311 Atm/Surf Probe (Cosmos 167) 1967 Venera 12 Flyby/Lander [imager failed] 1978 3V No.631 Atm/Surf Probe (Cosmos 359) 1970 Venera 13 Flyby/Lander 1981 3V No.671 Alm/Surf Probe Cosmos 482) 1972 Venera 14 Flyby/Lander 1981 Venera 15 Orbiter 1983 Venera 16 Orbiter 1983 Vega 1 Flyby/Lander/Balloon 1984 Vega 2 Flyby/Lander/Balloon 1984

[1] To measure the temperature, pressure, wind speed and direction on the surface, and to measure the chemical composition of the atmosphere around the planet

[2] To achieve soft landings at chosen sites and take pictures of the surface to study the terrain and vegetation

[3] To measure the composition, bearing strength and properties of the soil

[4] To measure the radiation levels and magnetic field at the surface

[5] To detect any traces of micro-organisms in the soil

[6] To study the upper atmosphere

[7] To compile a detailed thermal radiation map from orbit

[8] To fly past Phobos and Deimos while in Mars orbit and take pictures to define their shape, size and albedo

[9] To photograph Mars from orbit in order to understand the nature of the seas’ and canals’ and to acquire information on seasonal changes.

These were extraordinarily demanding objectives for a program that had endured six failed missions since 1960 and had yet to achieve anything at all at Mars. In one bold leap, compelled by competition with the US and enabled by the Proton-K launcher, the Soviets would attempt the first Mars orbiters and landers at a launch

Tikhonravov, Mikhail Klavdievich 1900-1974

Deputy Chief Designer OKB-1 1956-1974

Although not chief of a design bureau, Mikhail Tikhonravov was a key member of Korolev’s team in the early days of OKB-1, and one of the pioneers of the Soviet space program. lie was an early glider enthusiast and worked with N. N. Polikarpov in the 1920s developing aircraft. In 1932 he joined GIRD and became interested in the theory of rocket flight and space technology, working with Korolev to build the first Soviet liquid propellant rocket.

Tikhonravov escaped the terror of the late 1930s and during WW-II worked on Katyusha rockets and a rocket-powered fighter. After the war, he was fascinated with the German V-2 rocket and designed his ота liigh-altitude rocket for carrying a pilot into space. In late 1946 he became Deputy Chief of NII-4 in Moscow to manage research into ballistic missile development. There he began a pioneering study into multistage rockets and orbital flight that would later be applied in launch vehicle and spacecraft development. Following Tsiolkovsky, he originated the concept of ’packet’ design for multistage rockets adopted by Korolev for the R-7. On November 1, 1956, he was transferred to OKB-1 where he worked hand-in-hand with Korolev in developing robotic spacecraft for flights to the Moon, Venus and Mars, and space­craft for OK II-1 ‘s manned spaceflight program.

Mishin, Vasily Pavlovich 1917-2001

Chief Designer OKB-1 1966-1974

As Korolev’s deputy and protege, Vasily Mishin took over management of OKB-1 after his mentor’s unfortunate death during surgery in 1966. Tt was during Mishin’s tenure that OKB-1 attempted to develop Korolev’s giant N-l Moon rocket and the Soyuz spacecraft to send cosmonauts to the Moon.

When he took over, the project was plagued with technical problems and unrealistic schedules. Mis­hin was a well-regarded engineer and a kindly man, but did not possess Korolev’s leadership talent, nor the charisma and connections that Korolev used to mobilize the massive Soviet political and industrial
machine and to thwart his enemies. While NASA succeeded with Apollo, Mishin oversaw four disastrous N-l launch attempts, failures in lunar Soyuz test flights, failures in three space station missions, and the deaths of the pilot of Soyuz 1 in 1967 and the three-man crew of Soyuz 11 in 1971. He was deposed in 1974 by a coup orchestrated by Korolev’s bitter rival, Valentin Glushko. Two years later any further attempts to send cosmonauts to the Moon were terminated.

Mishin was exiled to the Moscow Aviation Institute and blamed as “the man who lost the Moon race”. He was unfortunate to have been the man in charge when the ambitious technological challenges began to crumble in the face of the relentless American Apollo juggernaut; he just didn’t have the ‘right stuff to overcome them. Although many in the West thought that he had been executed. Mishin resurfaced in the late 1980s and published a number of controversial accounts of the history of the Soviet space program.

Glushko, Valentin Petrovich 1908-1989

Chief Designer OKB-456 1946-1974 Chief Designer NPO-Energiya 1974-1989

A contemporary of Korolev, Valentin Glushko began working on rocket engines in the 1920s and became head of the Gas Dynamics Laboratory. The military merged it with Korolev’s GIRD rocket research group in the 1930s. Like Korolev, Glushko was a victim of the purges. After WW-II he was made head of Design Bureau OKB-456 to develop rocket engines for missiles designed by Korolev’s OKB-1, Chelomey’s OKB-52 and У angel’s OKB – 586. When Korolev began to design a successor to the R-7 and ignored Glushko’s advice to use hypergolic propellants they became bitter enemies.

In fact, the animosity between the two harked back to the purges. Korolev w? as convinced that Glushko was responsible for his internment. Glushko was arrested first, and there is a story that under duress he denounced Korolev for undermining progress by preferring liquid rather than solid fuel rockets, and shortly thereafter Korolev was arrested. Glushko criticized Korolev’s plans for the Moon program and impeded Korolev’s progress by refusing to build the engines for the N-l, forcing Korolev to resort to an inexperienced supplier.

In 1974, with the N-l suffering spectacular failures, OKB-1’s enemies, including Glushko and Chelomey, convinced Brezhnev to fire Mishin. Glushko was appointed m Mishin’s place. TIis first act was to precipitously cancel the N-l program. Tie then absorbed OKB-1 into his own design bureau OKB-456. On gaining membership of the Central Committee of the Communist Party he also absorbed Chelomey’s design bureau to create a massive rocket engineering empire named NPO-Energiya. Then,
having defeated the legacy of Korolev, Glushko focused on building a new rocket and reusable spacecraft system in his own image – the Energiya and Buran – to replace the Soyuz system and compete with the US Space Shuttle. The Energiya rocket flew7 twice in the late 1980s and Buran once, unmanned, and were promptly canceled as unaffordable. They arc now’ only silent monuments to a man described by his critics as vain, stubborn, petty and manipulative. Nevertheless, the Energiya- Buran project is a monument to the skilled people in the Soviet Union who made this ambitious and complex project possible. By supreme irony, today Korolev’s Soyuz rocket and spacecraft arc still in front line service and the conglomerate that Glushko built bears Korolev’s name as the S. P. Korolev Rocket and Space Corporation Energiya.

Glushko was a superb engineer and designer of rocket engines and his OKB-456 created some of the most efficient engines ever produced. He managed to build closed-cycle engines that eluded the skills of American rocket engine makers. At the same time he was a stubborn critic of cryogenics, even though he built engines using liquid oxygen, and insisted that hydrogen was not a suitable rocket fuel while the US was using it for the upper stages of its most powerful launch vehicle, the Saturn V. Unable to eliminate combustion instability in large single-chamber engines, Glushko devised an ingenious solution using four smaller combustion chamber/nozzles which shared a common fuel/oxidizer feed. The four-chamber RD-107 and 108 engines he built for the R-7 are still in use today with the Soyuz launcher. In one of the ironies of the Cold War, the very powerful four-chamber RD-170 engine that he made for the Energiya rocket wras split in two and the two-chamber variant, the RD-180, is now7 in service powering the latest model of the US Atlas launch vehicle!

Chelomey, Vladimir Nikolaevich 1914-1984

Chief Designer OKB-52 1955-1984

Vladimir Chelomey, a mathematician dealing with non-linear w7ave dynamics, began his career work­ing on cruise missiles. In 1955 he became head of OKB-52, and in 1958 began work on his first ICBM, the UR-100 (NATO designation SS-11), which became the Soviet Union’s answer to the US Minuteman. While Korolev never lost his prefer­ence for cryogenics, both Chelomey and Mikhail Yangel opted for storable propellants and their missiles were better suited to military requirements.

This led Korolev to focus on the politically – supported lunar cosmonaut program. Chelomey’s attention to military requirements gained him respect in the military establishment and access to far greater resources than Korolev.

In the early 1960s, Chelomey began development of the UR-500 Proton rocket intended to be a heavy lift ICBM. When the military canceled it, Chelomey, with

Keldysh’s support, used his political connections to save it for the Moon program. Chelomey had a rival plan to Korolev’s for development of rockets and spacecraft to take cosmonauts to the Moon. He proposed his plan in competition to Korolev when the USSR finally made its decision in 1964 to compete with the US Apollo program. Khrushchev (whose son was an engineer at OKB-52) was indebted to Chelomey for providing practical and vital military ICBMs, and so Chelomey managed to have his UR-500 chosen in preference to Korolev’s newr design for the test and circumlunar phases of the manned lunar program. However, the spacecraft would be the lunar Soyuz that Korolev proposed, and Korolev’s massive N-l Moon rocket was selected over Chclomey’s even larger UR-700 for the lunar landing missions. The Chclomey-Korolcv rivalry continued as both programs were separately managed and funded by Khrushchev and later by Brezhnev in a process that divided the backing required for an efficient and timely outcome. After a long run of early failures, the Proton was used to launch an automated Soyuz test spacecraft under the cover name of Zond on llights which looped around the Moon and returned to Earth. It went on to launch heavy satellites and modules for the Salyut and Mir space stations. Georgi Babakin at ihe Lavochkin Design Bureau, who had inherited Korolev’s robotic exploration program, recognized that the Proton was well suited to launch the heavy spacecraft that he was designing and, with upper stage modifications which included using one of the stages from Korolev’s N-1 rocket, the Proton became the launcher of choice for the Soviet lunar and planetary spacecraft of the 1970s and beyond. It is today a world standard for commercial heavy launch services.

Bahakin, Georgi Nikolayevich 1914-1971

General Designer NPO-Lavochkin 1965-1971

As a self-taught engineer, Georgi Babakin did not gain a college degree until the age of forty-three. He worked on rocket control systems at N11-88 from 1949 to 1951, where he first met Korolev, and then designed military missile systems at OKB-301 for Chief Designer Semyon A. Lavochkin, where he rose to become a deputy chief designer and then General Designer (Director) of OKB-301, now – renamed NPO-Lavochkin. Meanwhile, OKB-1 had become overwhelmed with responsibility for both manned and unmanned programs, and was suffering a run of failures. Trusting Babakin implicitly, Korolev trans­ferred all robotic lunar and planetary space probes to Lavochkin. Subsequently, Babakin solved the quality control problems plaguing the Luna Ye-6 and 3MV planetary spacecraft, leading to a long run of successes at the Moon and Venus. The heavy Proton-launched, spacecraft were developed under his direction and he experienced their initial success with the Luna 16 sample return and Luna 17 rover.

He was a worthy successor to Korolev, but died suddenly at the early age of fifty-seven in August 1971 before his new Mars spacecraft reached their destinations.

Kryukov, Sergey Sergeyevich 1918-2005 ‘

General Designer NPO-Lavochkin 1971-1977

Sergey Kryukov worked with Korolev, Tikhonra – vov and Mishin on the development of the R series of rockets, and rose to deputy chief designer to Korolev along with Mishin and others at OKB-1.

He had a falling out with Mishin over development of the Block D upper stage for the N-l (also used on the Proton) and transferred to Lavochkin. After less than a year, he became General Designer when Babakin died. He inherited the problems that would plague the Mars program and the successes that would come in the Venus program. After the 1973 Mars fleet disaster, he was tasked by Afanasyev to design new and even larger Mars missions to send rovers to the surface and to return samples. These missions turned out to be Loo complex and costly for the traumatized post-Apollo Soviet space program and were canceled in 1977 in favor of the rather less ambitious Phobos mission. Kryukov was replaced by Vyacheslav Kovtunenko and transferred to Glushko’s organization, where he worked until retirement in 1982.

Kovtunenko, Vyacheslav Mikhailovich 1921-1995

General Designer NPO-Lavochkin 1977-1995

While working for Yangcl’s design bureau, Vya­cheslav Kovtunenko designed the Cosmos and Tsyklon rockets and was responsible for the Intercosmos series of small science satellites. On succeeding Kryukov as Director of Lavochkin, he developed the new generation Universal Mars Venus Luna spacecraft, which was essentially a renovation and upgrade of the heavy Venera spacecraft. He encountered obstacles to funding, not faring well against industry heavyweights such as Glushko, and the first of the new spacecraft was unable to be launched until 1988, as the Phobos mission. Kovtunenko would guide Lavochkin through the successes of Venera 11 to 16 and Vega 1 and 2. and the partial failures of Phobos 1 and 2, and the transition from the USSR to Russia leading up to the final Mars-96 debacle. He died in office in 1995.

DIRECTORS OK THE SCIENCE INSTITUTIONS

Petrov, Georgi Ivanovich

1912-1987

Director of the Institute for Space Research (ІКГ) 1965-1973 ‘

A brilliant aerodynamics engineer having contrib­uted significantly to ICBM design, Georgi Petrov was selected in 1965 by Keldysh to be the first Director of the newly formed Institute for Space Research. Petrov worked hard to establish his institute iii the panoply of scientific communities, all of which were scrambling for funding in the new scientific space program. It was several years before IKI developed into a world-class institute for space research and the building of scientific instruments for space science missions. He established highly capable teams of space scientists and engineers and successfully motivated them to explore near-Earth space, the Moon, and the planets. IKI benefited immensely from his leadership, and mirrored his style of creativity and open discussion.

Sagdeev, Roald Zinnurovich 1932-present

Director of the Institute for Space Research 1973—

1988 ‘

Roald Sagdeev was a nuclear physicist working in the remote ‘science city’ of Akademgorodok when, at the advice of the distinguished physicist Leo Artsimovich, he was tapped by Keldysh to replace Petrov at IKI. He took leadership of IKI as the second generation of heavy Venus spacecraft was being introduced by Lavochkin, and shared in its success. He reassigned planetary geology to the Vernadsky fnstitute and focused his own institute’s scientific efforts on planetary atmospheres and space plasma. These two institutes became domi – Sagdeev

nant and competitive centers for planetary science.

IKI remained the center for space astronomy.

A hallmark of Sagdeev’s experience in a ‘science city’ far from the Kremlin was a culture of open, questioning discussion with promotion on the basis of merit rather than on political connection. Although upon becoming Director and a member of the Communist Party he initially conformed to the Soviet system, he later imported the Akademgorodok attitudes to IKI, bringing perestroika (transformation) and
glasnost (openness) to his institute before Mikhail Gorbachov introduced it to the USSR. His most remarkable and enduring achievement was the opening of the Soviet planetary exploration program to international participation, leading his country into an era of scientific mission cooperation with the West as perestroika was driving the Soviet Union. Succeeding through charm, patience and shrew’d political judgment, first the Vega Vcnus-Halley mission and then the Phobos Mars mission were approved as progressively more open to international scientific participation. He was aided by the mass and size of Soviet spacecraft, which were able to accommodate a large number of foreign instruments to undertake comprehensive scientific missions. The new policy was highly successful at the outset, catching the US in the doldrums after its successes of the 1970s, and the Soviets overtook the US as international leader of planetary exploration in the 1980s.

After the success of the Vega missions in 1986, Sagdeev became a local hero and international celebrity. But the joy was short lived. The loss of the Phobos missions in 1988 raised an international furor in the space science community. This was not a comfortable situation for Sagdeev and he left IKI in 1988, married the daughter of Dwight Eisenhower, and moved to the US to become a Professor at the University of Maryland. He remained a force in international space science and exploration for a time, but his inll uence on space policy decreased as he focused his efforts more on East-West relations. The high level of international participation in the Vega and Phobos missions, and the ensuing Mars-96 mission, has never been equaled.

Vinogradov, Aleksander Pavlovich 1895-1975

Director of the Vernadsky Institute of Geochemical and Analytical Chemistry 1947-1975

Alexander Vinogradov was the Soviet Union’s leading geochemist, head of the Vernadsky Institute and Vice President of the Soviet Academy of Sciences at the opening of the ‘space age’, and Chairman of the Moon and Planets Section of the Space Council MNTS KI. He was a pioneer in using chemical and isotope analysis to study the formation of minerals in Earth and meteoritic materials. He developed the use of gamma-ray spectroscopy to study the composition of planetary surfaces, and analyzed samples returned from the Moon. Under his leadership, the Vernadsky In­stitute developed many of the geochemistry instru­ments flown on missions to the Moon, Venus and Mars.

Barsukov, Valery Leonidovich 1928-1992

Director of the Vernadsky Institute 1976-1992

Valery Barsukov was a geologist experienced in field work. After taking over the Vernadsky Institute and its new role in planetary geology in 1976, he promoted missions and flight experiments with geochemical goals. He assumed leadership at a time when Mars exploration was in decline and Venus exploration was dominating the planetary program. He was an effective lobbyist for planetary geology missions and proved an effective rival to the Institute for Space Research led by Sagdeev.

Both Barsukov and Sagdeev were well connected and fought, sometimes bitterly, to establish their own space science missions.

With Sagdeev’s departure in 1988, Barsukov and the Vernadsky Institute assumed effective leadership of the Soviet planetary exploration program. Until his death in 1992, Barsukov pursued a complex Mars exploration plan even more international in scope than Sagdeev’s Phobos mission, with a particular focus on US involvement. Under the joint leadership of Barsukov from Vernadsky and Professor James Head from Brown University, the Vernadsky-Brown Symposium on Cosmochemistry was organized. This continues to function as a forum for Russian-American cooperative research in lunar and planetary science.

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The Ye-8 series were much heavier and more complex, and were launched on the powerful new Proton rocket. The design centered on four large spherical propellant

tanks connected in a square using cylindrical inter-tank sections. The landing system and engine were mounted on the underside of this assembly and the lander payload on the upper side.

The principal goals of these spacecraft were first to deploy a lunar rover on the surface (the Ye-8 model) and second to return samples of the lunar surface to Earth (the Ye-8-5 model). Three Ye-8 lunar lander rover spacecraft were launched, two of which, Luna 17 and Luna 21. were successful. Of a total of eleven Ye-8-5 sample return spacecraft launched, only three were successful, Luna 16, 20 and 24. In fact, Luna 20 and 24 were advanced Yc-8-5M models. Two additional Ye-8 models were modified as Yc-8LS lunar orbiters and both flown successfully as Luna 19 and 22. The overall record for the Yc-8 was therefore seven successes of sixteen attempts.