Category Soviet Robots in the Solar System

R-7 ICBMS AND SPUTNIK

The first ICBM built in the USSR was the R-7, affectionately named Semyorka’ by its makers. It was designed and built by Sergey Korolev’s design bureau, OKB-1, in great secrecy in the 1950s. Its multi-stage design was quite different than the scheme used in the IJS where the stages were stacked on top of one another. The R-7 used a ‘packet’ design in which identical propulsion units were clustered around a central core unit and dropped from the core after burnout. The core continued to burn as the second stage. This concept was suggested by Tsiolkovsky, and championed by M. K. Tikhonravov working at the Defense Scientific Research Institute (NII-4) starting in the late 1940s. Korolev adopted the idea at OKB-1, and in the early 1950s directed feasibility studies by Keldysh’s Department at the Mathematics Institute (MIAN) of the Soviet Academy of Sciences to examine the utility of variants of the scheme. In 1952, work at these three institutes resulted in a preliminary design that evolved tw о years later into the definitive design of the R-7. The Soviet government approved construction of the R-7 on May 20. 1954. with the project designation 8K71. *

The R-7 launcher had a central core propulsion unit 33 meters tall, including the w arhead, with four identical strap-on booster propulsion units around the bottom 20 meters. Each strap-on unit w’as an integral propulsion stage with an RD-107 engine and its own tanks for kerosene and liquid oxygen. The central core was powered by a nearly identical RD-108 engine delivering somewhat less thrust but sustained over a longer time and optimized for high altitudes. Each RD-107 had a pair of gimbaled vernier engines for steering and trim, and the RD-108 had a set of four such engines. The main engines were built by Valentin Glushko’s OKB-456. and each had a cluster of four combustion chambers fed by a single turbopump. All engines, boosters and core, operated for lift-off. The four boosters would burn for about 2 minutes before dropping off, leaving the central core as the second stage sustainer, which continued for several minutes until it had achieved the required velocity and altitude.

The first model of the R-7 was delivered in December 1956 and used for captive tests. The first flight model followed in March 1957. The first three launch attempts failed. On the first, on May 15. 1957, the flight was cut short after 103 seconds when a booster engine failed. The second vehicle was removed from the pad on June 11 after three aborted launch attempts. The third attempt on July 12 failed when the vehicle began to rotate rapidly and shed its boosters. The fourth attempt on August 21 was a qualified success, with the rocket delivering the payload along the desired trajectory, but the payload disintegrated during re-entry. A fifth test on September 7 led to the same result. In these latter tests, how ever, the rocket itself had performed satisfactorily.

R-7 ICB Ms and Sputnik 35

image25

From the very beginning of ICBM development in the late 1940s, Korolev clearly had in mind using his rocket to access space. He repeatedly lobbied the government for support and on January 30, 1956, in response to a letter to the Politburo signed by Korolev, Keldysh and Tikhonravov, a decree was passed for the development of an artificial satellite designated Object D and a special version of the R-7 to launch it. With Object D development proceeding rather slowly, Korolev, fearing that von Braun in America might place the world’s first satellite into orbit, was eager to try to

do so while his R-7 was undergoing its early test flights, and he decided to launch a very simple satellite, essentially a small sphere containing a radio transmitter, after the first successful test flights. Launch vehicle 8K71PS serial number Ml-IPS (PS for ‘Prostcishyi Sputnik*. meaning provisional satellite) was modified by removing unnecessary warhead targeting equipment and test instrumentation, reprogramming the burn sequence, and replacing the dummy warhead with the satellite and shroud. It lifted off on October 4, 1957 and opened the ‘space age’ by placing Sputnik into a slightly lower orbit than planned after the sustainer shut down 1 second early.

Phobos and Mars 96, 1988-1996

After a long run of very successful Venus missions beginning in 1967. including the highly successful Vega mission in 1985, and the clear lack of American follow-up to the Viking Mars orbiter/landers, the Soviets took the opportunity in the late 1980s to resume Mars missions. A new Universal Mars Venus Luna (UMVL) spacecraft was developed based on the highly successful Fro ton-launched Venera series. Two such spacecraft were built for the 1988 Mars opportunity, for a mission that would focus on the Martian moon Phobos. Once a spacecraft was in orbit around the planet, it would make a series of close encounters with Phobos, coming ever closer. When the geometry was just right, active remote sensing experiments would blast material off the surface of Phobos and two small landers would be deployed, one stationary and the other mobile. It was to be a very ambitious mission, including instruments from many international partners.

The Phobos 1 spacecraft w? as lost to a command error during the interplanetary cruise. Its partner achieved Mars orbit and returned very useful remote sensing data on Mars as it trimmed its orbit to approach Phobos. Unfortunately, communica­tions with Phobos 2 w^ere lost just days before its first planned rendezvous, and only very limited remote sensing data on this target were transmitted.

Encouraged by the Phobos effort, a Mars orbiter and ambitious surface mission w’as planned. This w’as originally scheduled for launch in 1992 using a new’ version of the IJM VL spacecraft but budget constraints led to it being descoped and slipped to

image50

Figure 5.13 The UMVL Phobos spacecraft.

image51

Figure 5.14 The Mars-9f> spacecraft (courtesy NPO-Lavochkin).

1994, and then further delayed to 1996. In addition to a large orbital science payload, the orbitcr had two small soft-landers similar to the previous Mars landers and two penetrators. This project involved even more international cooperation than the Phobos effort. However, this time only a single spacecraft wras built, and when it was launched on November 16, 1996. failures in the control system between the spacecraft and the Block D upper stage resulted in the escape burn causing re-entry. Having lost Mars-96 so embarrassingly, the Russian planetary exploration program entered a hiatus which continued through the end of the 20th Century. It is scheduled for renewal with the planned launch of the Phobos-Grunt sample return spacecraft in late 2011.

THE YE-6M LUNAR LANDER SERIES: 1966

Campaign objectives:

Throughout 1965 there was a high level of frustration in the Soviet robotic lunar and planetary programs. In the period 1963-65, three of six Venus-type spacecraft were successfully dispatched, two of three Mars-type, and live of eleven soft landers for the Moon. Nevertheless, all of these spacecraft failed either in transit or at the target. Only one, Zond 3, a test launch to Mars distance, returned anything of scientific or propaganda value, and that was from its flyby of the Moon. On the plus side things were improving, because three missions in late 1965 reached their targets and failed only at the last minute, Venera 2 and Luna 7 and 8.

Spacecraft launched

First spacecraft:

Luna 9 (Ye-6M No.202/13)

Mission Type:

Lunar Lander

Country j Builder:

X JSSR/NPO-Lavoch ki n

launch Vehicle:

Molniva-M

Launch Date: Time:

January 31, 1966 at 11:41:37 UT (Baikonur)

Landing Date: Time:

February 3, 1966 at 18:44:54 UT

Mission End:

February 6, 1966 at 22:55 UT

Outcome:

Success.

Second spacecraft:

Luna 13 (Ye-6M No.205/14)

Mission Type:

Lunar Lander

Country j Builder:

lJSSR/NPO-Lavoch ki n

launch Vehicle:

Molniva-M

Launch Date/ Time:

December 2L 1966 at 10:17:00 UT (Baikonur)

Landing Date; Time:

December 24. 1966 at 18:01:00 UT

Mission End:

December 28. 1966 at 06:13 UT

Outcome:

Success.

When responsibility for robotic lunar and planetary missions was transferred from ОКБ-1 to NPO-Lavochkin at the end of 1965, a dozen failed missions made Georgi Babakin decide to modify the Ye-6 lander as the Ye-6Mi. His changes produced an immediate success, with Luna 9 making the desired soft landing on February 3, 1966, and sending back the first pictures from the surface of another world. Once again the Soviets had beaten the US to a space exploration milestone. Western headlines proclaimed a new space lead for the LTSSR. Although several years behind schedule, largely owing to the difficulty in developing the upper stage for its launcher, the US succeeded at its first attempt at a lunar landing. Surveyor 1 touched down on June 2, 1966, and returned imagery of a far superior quality. In December 1966 the second and final lander in the Ye-6M scries, Luna 13, was successful as well.

Spacecraft:

The Ye-6M spacecraft was identical to ihe Ye-6 with modifications to the landing shock absorbers and a new independent guidance system. The airbags that enclosed the lander were inflated after the retro-rocket had ignited, requiring relocation of the tank of the nitrogen with which to inflate the bags from one of the side modules onto the cruise stage itself, because the side modules were jettisoned prior to braking. No additional redundancy was introduced.

Luna 9 launch mass: 1,538 kg (lander 105 kgj

Luna 13 launch mass: 1,620 kg (lander 113 kg)

image87

Automatic Lunar station (ALS)

 

Guidance system module (MOO)

 

Detachable module *2 with

radio equipment

 

THE YE-6M LUNAR LANDER SERIES: 1966

Radio altimeter

 

Engine installation

 

image89

Figure 10.2 Luna 9 spacecraft diagram (courtesy Energtya Corp).

 

image88

Two-edged

mirror

 

Figure 10.3 Luna 9 lander.

 

image91

Figure 10.4 Luna 13 lander (from Space Travel Encyclopedia)-. 1. Transmitter antennae; 2. Receiver antennae; 3. Deployment arm; 4. Penetrometer; 5. Gamma-ray densit­ometer; 6. Panoramic stereo cameras; 7. Infra-red radiometers; 8. Stabilizing petals.

 

image90

The Luna 9 lander had a mass of 105 kg. including 5 kg of scientific instruments. At 112 kg. the Luna 13 lander carried an increased scientific payload including two panoramic cameras for stereoscopic imaging and a pair of spring-loaded deployable

1.5 meter long bootns for testing soil mechanics.

image92

Figure 10.5 Luna 9 lander with single camera, and Luna 13 lander with dual-camera (inset).

Payload:

Luna 9:

1. Panoramic camera

2. Radiation detector

The scanning photometer camera system of Luna 4 to 8 was improved. It weighed only 1.5 kg, drew only 2.5 W, and had higher resolution. It used a lilting mirror in a revolving turret to produce a 29 x 360 degree panorama of 6,000 lines. The sensitivity could be adjusted by command, and it could operate from 80 to 150,000 lux. A panorama required approximately 100 minutes to transmit as 250 Hz analog video on the 183.538 lVIFTz channel. Optical calibration and tilt-indication targets were suspended from the pop-up antennas, and three short poles carried dihedral mirrors to provide stereo images for small areas of the surface, to measure distances, and to locate the horizon and tilt more precisely. The radiation detector measured solar corpuscular radiation both in flight and on the lunar surface.

Luna 13:

1. Dual panoramic cameras for stereo

2. Radiation detector

3. Infrared radiometer for soil temperature

4. Penetrometer for soil strength and bearing capacity

5. Gamma – г а у га dia ti on/ backsca tter densi tometer

6. Three axis accelerometer for surface mechanics on landing

The penetrometer, which had a 5 cm long cone, was mounted at the end of one of the deployable booms and a 65 N explosive charge drove it into the ground in order to measure the mechanical soil properties. The gamma-ray backsca tter densitometer was mounted at the end of the other boom to measure soil density.

Mission description:

Launched on January 31. 1966, the Luna 9 spacecraft flew flawlessly across cislunar space, made its braking maneuver and ejected its capsule, which bounced and rolled to a halt at 18:45:04 IJT on February 3 at 7.08°N 295.63 H in the Ocean of Storms. After the four petals opened outward and stabilized the capsule, the spring-loaded antennas were commanded to deploy, with one evidently failing. Five minutes after touchdown the television camera was activated to show the first ground-level view of the lunar surface. At that time the Sun was just 3.5 degrees above the horizon and much of the ground was in shadow. In one of the ironies of the Cold War. the British using the Jodrell Bank radio telescope were the first to publish pictures from Luna 9. after intercepting and readily recognizing the transmission as a fax machine signal. Although the Soviets had published their frequencies and had enlisted the assistance of Jodrell Bank to track previous missions, they were understandably upset to have their accomplishment ‘scooped* in the world’s press, particularly as the aspect ratio was incorrectly set. The US intelligence station at Asmara, Ethiopia, also intercepted the images but this was not made known at the time.

Luna 9 came to rest near the rim of a 25 meter diameter crater and w as lilted at 15 degrees. Over the next few hours it settled to a tilt of 22.5 degrees, enabling stereo images to be made of nearby features. Over seven communications sessions lasting a total of 8 hours and 5 minutes four panoramas were transmitted, the final one with the Sun approaching an elevation of 40 degrees. The last contact w as at 22:55 UT on February 6, as the battery depleted.

The second Ye-6M spacecraft, Luna 13. landed at 18:01:00 UT on December 24. 1966, at 18.87 N 297.95"E between the craters Seleucus and Krafft in the Ocean of Storms. In the act of bouncing and rolling, the accelerometer recorded data on soil density to depths of about 20 cm. It deployed tw o booms to measure soil density and surface radioactivity. The television system provided imagery at various times over

the next 2 days, but the failure of one of the two cameras precluded stereo imagery. The depletion of the battery terminated operations at 06:13 IJT on December 28.

Results:

Luna 9:

Nine images were returned by Luna 9, including five that were assembled to provide a panoramic view of the surface in the vicinity of the lander. The radiation detector measured a daily dosage of 30 millirads, which would not be hazardous to humans. The successful landing was clear evidence that the lunar surface was sufficiently dense to support a future manned spacecraft.

image93

Figure 10.6 Portion of a Luna 9 panorama.

image94

Figure 10.7 Portion of a Luna 13 panorama.

Luna 13:

Only one camera worked on Luna 13, returning five 220-degree panoramas in which the Sun was at increasing elevations. The soil density was found to be approximately

0. 8 g/cc, much less than lunar bulk density and terrestrial analogs, but sufficient to support heavy landers. The radiation detector confirmed the 30 n і Hi rads day reading by Luna 9. The infrared radiometer recorded surface temperature as a function of solar elevation, measuring a temperature of 117°C at local noon. It was decided that the first cosmonauts to land on the Moon would do so in the Ocean of Storms.

Surface topography

Altimetry based on the column density of carbon dioxide measured by the infrared photometer in the 2.06 micron absorption band was obtained along the orbiter tracks across the surface. The inferred altitudes were in general agreement with terrestrial radar observations.

Surface properties

The large diurnal variations of surface temperature indicated a low’ heat conductivity characteristic of a dry and dusty surface. Latitudinal surface temperature variations ranged from -110°C at the northern polar cap to + 1VC near the equator. Hquatorial temperatures averaged -40°C, and at 60°S latitude they were -70°C without much diurnal variation. Dark areas on the surface were 10 to 15 degrees warmer than the light areas. The surface cooled rapidly during the night in low latitudes, indicating a dry, porous soil with a low thermal conductivity. Subsurface temperatures down to a depth of 0.5 meter were no higher than -40°C. There were thermal ‘hot spots’ some 10°C warmer than their surroundings. Temperatures at the northern polar cap were close to the carbon dioxide condensation temperature. Surface pressures of 5.5 to 6 millibars ‘лете measured. Soil density, heat conductivity, dielectric permeability and reflectivity were derived from microwave and thermal radiometry. Soil densities of 1.2 to 1.6 g/cc were reported, with values increasing to

3.5 g/cc in some places. The surface was presumed to be covered with silicon dioxide dust to an average depth of about 1 mm. Heat flow anomalies on the surface were discovered.

Global properties

Global data on the Martian gravity and magnetic fields was acquired. No intrinsic planetary magnetic field was detected, and plasma data for the interaction of the ionosphere with the solar wind indicated a magnetic moment at least 4,000 times weaker than that of Earth. A key discovery were large local mass concentrations in the gravity field, similar lo Ihose of the Moon, which created significant changes in the orbits of the spacecraft. In addition, the polar diameter was measurably less than that at the equator.

Landers:

Although the Mars 2 lander crashed, it is significant as the first human artifact to reach the surface of Mars.

The Mars 3 lander gained the distinction of being the first successful landing on Mars, but it fell silent almost immediately. Figure 12.19 shows the data returned by

image165

Figure 12.19 Image from the Mars 3 lander.

the scanning-photometer imager, released in recent years, which analysis indicates to be mostly noise.

The last gasp: Mars-96

TIMELINE: 1989-1996

The Soviet Union had planned to follow up their Phobos mission with a surface investigation of Mars. This was originally scheduled for launch in 1992 but funding was delayed and the launch date had to be postponed until 1994. The plan called for two orbiters to be launched in 1994., each of which would deploy a balloon into the atmosphere and small landers onto the surface, the launch of two orbiters in 1996 to deploy rovers onto the surface, and the launch of a sample return mission in 1998. In a revision, the plan was descoped to a single orbiter in 1994 carrying small landers and penetrators and a second orbiter in 1996 carrying the balloon and a rover. After the fall of the Soviet Union, further funding difficulties in the new Russia resulted in the launch of the 1994 mission being postponed to 1996 and the launch of the 1996 mission being postponed to 1998. But the technical and funding problems involved in building Mars-96 made it obvious that the 1998 mission would never materialize. The continuing problems with Russian suppliers and with government funding for development and test were frustrating to the Russians, and a source of consternation to the international community supplying science investigations for the mission. All of which led to massive disappointment when the launch failed on November 16, 1996. The propulsion sequence involving the second burn of the Block D stage and subsequent boost by the spacecraft’s own Fregat propulsion module went awry.

The loss of Mars-96 was tragic for the Russian planetary exploration program that had been losing support in the fiscally strapped government. The US had suffered its iirst major tragedy at Mars in 1993 with the loss of Mars Observer shortly prior to arrival at the planet. But the US had recovered, by establishing a new series of Mars missions and had launched the first one. Mars Global Surveyor, 9 days prior to the Mars-96 debacle. The Mars Pathfinder mission was launched on December 4, and went on to successfully land on the planet and deploy a small rover, thereby erasing a goal that the Russians had been working towards for more than a decade.

W. T. Huntress and M. Y. Marov, Soviet Robots in the Solar System: Mission Technologies,’vS ‘

and Discoveries, Springer Praxis Hooks 1, DOl 10.1007/978-1-4419-7898-1_20,

© Springer Science+Business Media, LLC 2011

Launch date

1989

Подпись: Successful radar mapper Success Multiple flybys, Hagoromo orbiter lost Подпись:Подпись: Success at Moon, failed on departureПодпись: Orbited Eros, touch-down finale Successful orbiter Fourth stage failure Successful lander, first Mars rover4 May Magellan Venus orbiter

18 Oct Galileo Jupiter orbiter/probc

1990

24 Jan Hiten lunar fiyby/orbiter

1991

No missions

1992

25 Sep Mars Observer orbiter

1993

No missions

1994

25 Jan Clementine lunar orbiter

1995

No missions

1996

17 Feb Near Earth Asteroid rdv

1 Nov Mars Globa] Surveyor

16 Nov Mars-96 orbiter/landcrs

4 Dec Mars Pathfinder lander/rover

Mars-96 was the last gasp in the storied history of Soviet lunar and planetary exploration in the 20th Century.

Soviet Robots in the Solar System

The competition between the United States and the Soviet Union in the Cold War produced one of the greatest adventures of exploration in the history of humankind. As a by-product of military competition between the two countries in weapon delivery systems and laying claim to the propaganda ‘high ground’, both countries applied themselves to the conquest of space by attaching civil payloads to their rockets in order to conduct both human missions in Earth orbit (and to the Moon in the case of the US Apollo program) and robotic missions beyond Earth orbit to the Moon and planets.

This book describes the 20th Century history of the Soviet adventure in robotic exploration of the Moon and planets. Our chronicle includes just those missions launched by the Soviets into deep space whose objective was to explore the Moon or planets. It does not include missions sent into deep space to study the Sun or Earth – Moon space environment. Test missions launched beyond low Earth orbit with operating lunar or planetary spacecraft, such as the Zond series, are included. Launch tests carrying non-operating model spacecraft are not included. We have endeavored to provide a comprehensive and accurate account of all relevant missions conducted between the year 1958, the date of the first Soviet spacecraft launch attempt to the Moon, and 1996. the date of the last Russian deep space mission to be launched in the 20th Century. All missions that were assembled on the launch pad with intent to fly are included. Some launch attempts suffered explosions on the pad, or shortly after booster ignition, or at some point during the flight of the launch vehicle. The Russians were particularly beset by launch vehicle failures, most often involving the upper stages.

There are inconsistencies in the data reported both in Western and Russian sources on Soviet lunar and planetary missions. We have attempted to provide the best possible information based on the published data and on interviews conducted with Russian participants in the former Soviet space program. In some cases w’e have made judgments to select what appears be the most accurate.

Wesley T. Huntress. Jr.

Mikhail Marov January 31, 2011

Acknowledgments

Wesley Huntress sincerely thanks the Geophysical Laboratory of the Carnegie Institution of Washington for his emeritus position, and also the Jet Propulsion Laboratory of the California Institute of Technology, Director Charles Elachi and Chief Scientist Moustafa Chahinc, for their support. Much of this book was written during the time spent at JPL as a Distinguished Visiting Scientist. I would also like to thank several friends who provided assistance, including Viktor Kcrzhanovich. Sasha Zakharov and particularly my co-author Mikhail Marov. Most importantly. I acknow ledge the patience and understanding of my wife Roseann while I w orked on this manuscript.

Mikhail Marov expresses his thanks to the M. V. Keldysh Institute of Applied Mathematics where he has worked for nearly 50 years as an Institute staff member involved essentially in all major endeavors of the Soviet robotic and human space program, and where he served as Scientific Secretary of the distinguished Space Research Council of the Soviet Academy of Sciences (MNTS Kl) that w as hosted by the Keldysh Institute while Mstislav Keldysh, its Director, and President of the Academy of Sciences, was Chairman of the Council. 1 would like to thank all my colleagues in the organizations of industry and Academy of Sciences, in particular in the S. P. Korolev Rocket-Space Corporation Energiya and Scientific-Industrial (NPO) Lavochkin Enterprise with whom 1 worked on space activities resolving numerous problems. I also thank my Russian friends who helped to find out and/or clarify historical data for this book, including Victor Legostaev, Vladimir Efanov. Igor Shevalev. Yury Logachev. Arnold Selivanov and Sasha Zakharov. Special thanks to Olga Devina who assisted me in data compilation and cross-examination. Finally, 1 appreciate Wesley Huntress’s kind invitation to participate in this project and co-author the book, as well as friendly cooperation and mutual understanding while working on the manuscript.

The illustrations in this book are mainly from governmental sources in the US. including NASA, and in Russia including Energiya. NPO-Lavochkin, the Institute for Space Science and the Institute of Geochemistry and Analytical Chemistry. We found the books ‘S. P. Korolev Rocket-Space Corporation Energiya. 1946-1996’ Volume 1, published by Menonsovpoligraph (1996), S. P. Korolev Rocket-Space

Corporation Energiya at the Boundary of Two Centuries. 1996-200Г Volume 2 (ed. Yu. P. Semenov). OOO Regent Print (2001), and ‘Automatic Space Vehicles for Fundamental and Applied Studies’ published by NPO-Lavochkin, MAI PRINT Moscow (2010) particularly useful. We appreciate the kind permission of V. P. Legostaev, the First Deputy of the President and General Designer of Energiya. and also of V. V. Khartov, the General Designer of NPO-Lavochkin, to reproduce photographs, diagrams and drawings from their organizations either published in their publications or placed on internet sites.

For non-governmental sources every effort has be made to trace the original copyright holders and seek formal permission for all figures that have appeared in previously published works. Л number of these images are from older and out-of­print books, and due to mergers and acquisitions in the publishing industry it has not been possible to track down all potential original copyright holders. We offer our apologies to any that we may have inadvertently overlooked. In all such cases we have cited the publication, author, or artist if known. We have used several unattributed drawings from the 1981 "Space Travel Encyclopedia (in Hungarian) by I. Almas and A. Horvath, others from the 1972 "Robot Explorers’ by Kenneth Gatland with art by John Wood and others, several by Ralph F. Gibbons from the "Soviet Year in Space’ series published by the American Astronautical Society, some drawings by Peter Gorin in Asif Siddiqi s ‘Challenge to Apollo and by an unattributed artist in the NASA "Pioneering Venus’ publication. Many thanks to Asif Siddiqi and Don Mitchell for permission to use material from their print and web publications. Special thanks to James Gary for pennission to use his art work and to Ted Stryk for images from the Soviet program that he has reprocessed with modern methods. Unfortunately, many of the older diagrams and images from the Soviet program are not the best quality for modern publication, but are illustrative of the times. Finally, thanks to David M. Harland for his diligent job of editing and his many improvements to the manuscript.

Pa

R-7E AND THE EARLY LENA PROBES

On March 8, 1957 Korolev’s OKB-1 founded a new department to develop manned satellites and spacecraft for lunar exploration. It was headed by Tikhonravov, and in April he submitted the first plans. These required that the basic 8K71 R-7 rocket be fitted with a third stage, and by the summer of 1957 technical plans were completed. The third stage would be mounted on top of the sustainer using an open truss so that its engine could be started before the sustainer was shut down – a measure designed to prevent the cavitation in the propellant tanks that would occur in zero-G if ignition were to be delayed until after the core stage had shut down.

Work began on two different vacuum-performance engines for the third stage, one by Glushko s design bureau, OKB-456, and the other by OKB-1 itself, working with Semyon A. Kosberg’s OKB-154 in Voronezh. The decision to build two versions of the third stage originated in a clash between Korolev and Glushko concerning the development of Glushko’s engine, resulting in a bitter rivalry that persisted through the development of the ill-fated N-l Moon rocket and contributed to the ultimate failure of the Soviet manned lunar program. Glushko wanted to develop a powerful 10-ton thrust engine using new hvpergolic fuels, unsymmetrical dimethlyhydrazine (UDMH) and nitric acid, instead of the standard kerosene fuel used by Korolev and Kosberg’s 5-ton thrust engine. However, Korolev was wedded to the LOX-kerosene combination and disliked Glushko’s toxic fuel, calling it “the devil s own venom”. He doubted that such a new engine could be developed in time for his schedule, which called for the first test of the three-stage rocket in June or July 1958, the launch of a lunar impact probe in August or September, and a flyby mission to photograph the far side of the Moon in October or November. He ordered the development of a 5-ton thrust engine at OKB-1 based on the R-7’s verniers. He was aware of developments at Kosberg’s aviation design bureau, w’hieh was working on a restartable LOX-kerosene engine using a new turbopump based on jet engine designs. To speed his ow7n development at OKB-1, Korolev engaged К os berg. As a neophyte in the rocket engine business, К os berg initially demurred, but Korolev persuaded him to collaborate on an engine that could operate in vacuum. For his part, Glushko was not happy with this parallel work, especially since OKB-154 was outside the circle of space developers. Glushko felt that he was due deference from Korolev, and he considered Korolev*s overtures to Kosberg an insult. But Korolev’s instincts proved correct. Glushko was struggling with problems when Kosberg’s engine became available for use in August 1958. It used a higher density kerosene to yield the needed thrust levels. The development of a third stage based on Glushko s engine was finally canceled in 1959.

Korolev’s ambitious schedule had to take second priority to developmental tests required to make the basic R-7 an operational ICBM. During the first half of 1958. his lunar plans were constantly threatened by difficulties with numerous changes to the engines and failures in development flight tests. A prototype of the lunar rocket with a dummy third stage equipped with avionics and telemetry, but no propulsion, was launched on July 10. 1958, powered by an improved set of booster and sustainer engines but these failed a few seconds into the flight, bringing down both the rocket and the timetable. Korolev shot for the Moon at the earliest opportunity on the very first flight of the new third stage on September 23, 1958. This and a second attempt on October 12 failed when the boosters fell apart and all flights had to be suspended until the problem was analyzed and fixed. Frustratingly, the cause turned out to be longitudinal vibrations in the strap-on boosters caused by the addition of the third stage. With this problem fixed, a third attempt failed on December 4, 1958, when the second stage engine shut down prematurely. On January 2, 1959. the rocket worked properly and although Luna 1 did not impact the Moon, the 6.000 km flyby was a sufficiently impressive achievement for the Soviets to declare that this had been the objective.

This R-7E. which tvas an 8K71 with a Block E third stage, was designated 8K72 and informally known as the ‘Luna’ launcher. It could put 6 tons into low Earth orbit and send 1.5 tons into deep space. It was used exclusively for the first generation of Luna probes in 1958 1960 including the successful Luna 1, 2 and 3. It came to an ignominious end with an explosive failure less than one second into the flight of the final such probe on April 19. 1960. The booster and core stages w’ere upgraded and the third stage improved, including upgrading its engine, to produce the 8K72K three-stage heavy lift orbital version of the R-7. This was used to launch the manned Vostok orbital spacecraft and the first Soviet photoreconnaissance satellites, known as the Zenit 2 series.

Breaking free of Earth

TIMELINE: AUG 1958-SEP 196ft

The space age began on October 4, 1957, with the launch of Sputnik during a test flight of Korolev’s new R-7 launcher. The ignition of the rocket’s engines on the pad in Baikonur on that day was the explosion that opened the floodgates of space exploration. A little over ten months later, on August 17, 1958, the first attempt was made to send a spacecraft to the Moon, a tiny orbiter, and this time launched by the US, but the rocket exploded. On September 23, the USSR attempted to send a lunar impactor to the Moon using a new variant of the R-7 augmented with a small third stage to reach escape velocity. The booster failed and was destroyed. The race to the Moon and planets was on.

In the three years 1958-1960, the US attempted nine times to send a small Pioneer class spacecraft to the Moon. All failed in one way or another. In the two years 1958-1959, the USSR also attempted nine times to send a spacecraft to the Moon. Of these, six were lost to launch vehicle failures, the Luna 1 impactor missed the Moon by 6,000 km, Luna 2 succeeded in impacting the Moon, and Luna 3 traveled beyond the Moon and sent back grainy pictures of its hitherto mysterious far side.

THE YE-1 LUNAR IMPACTOR SERIES: 1958-1959

Campaign objectives:

After the launch of Sputnik, Korolev took advantage of the world’s reaction to push the Soviet government into approving plans for non-military applications of his R-7 rocket, including lunar exploration. An earlier attempt in 1955 had been of no avail, but now’ the time was ripe. He established three new design groups at OK. B-1, one for

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 6,

© Springer Science+Business Media, LLC 2011

Подпись: Launch date 1958 17 Aug Pioneer lunar orbiter 23 Sep Luna impactor 11 Oct Pioneer 1 lunar orbiter 11 Oct Luna impactor 8 Nov Pioneer 2 lunar orbiter 4 Dec Luna impactor 6 Dec Pioneer 3 lunar flyby 1959 2 Jan Luna 1 impactor 3 Mai- Pioneer 4 lunar flyby 18 .Tun Luna impactor 12 Sep Luna 2 impactor 24 Sep Pioneer lunar orbiter 4 Oct Luna 3 circumlunar flyby 26 Nov Pioneer lunar orbiter I960 15 Apr Luna circumlunar flyby 19 Apr Luna circumlunar flyby 25 Sep Pioneer lunar orbiter
Подпись: Booster exploded First stage destroyed Reached 115,000 km altitude First stage destroyed Third stage failure Second stage premature shutdown Reached 107,500 km altitude Missed Moon by 5,965 km Missed Moon by 60,030 km Second stage guidance failure Successful lunar impact on Sep 14 Pad explosion during test Success, returned lunar far side images Shroud collapsed during launch Third stage malfunction First stage disintegrated Second stage malfunction

communications satellites, one for manned space flight, and the third for robotic lunar spacecraft. Mikhail Tikhonravov and Gleb Maksimov were in charge of the latter. Mstislav Keldysh provided specific scientific goals. After a few months work, Korolev and Tikhonravov sent a letter to Moscow on January 28, 1958, proposing a lunar impactor and a lunar flyby mission to photograph the far side. Korolev and Keldysh jointly convinced the government, and on March 20 approval was granted. In fact, lunar spacecraft designs were underway and in February Korolev had begun to develop the third stage required for his R-7 launcher. He was very aware of well – publicized plans in the US for a lunar orbiter to be launched in the summer of 1958, and he wanted to be first.

While preparing for the launch of the first spacecraft to the Moon in the summer, Korolev and Tikhonravov expanded the scope of their plan for the conquest of space by the Soviet Union. This plan was finished in early July 1958, but was held secret outside of a few people in the closed Soviet space circle. It called for upgrading the R-7 to three stages to launch robotic lunar landers and photographic flyby missions, then upgrading the R-7 again to four stages to launch spacecraft to Mars and Venus, and developing orbital rendezvous and other techniques and technologies to enable men to fly around and land on the Moon, as a precursor to creating a colony on the Moon and visiting Mars and Venus.

Maksimov and Tikhonravov also prepared detailed designs for five types of lunar spacecraft in the spring of 1958:

Ye-1 Lunar impact spacecraft, 170 kg

Ye-2 Lunar Гаг-sidc photographic flyby, 280 kg

Ye-3 Same as Ye-2 with improved photographic equipment

Ye-4 Lunar impact spacecraft with explosives, possibly nuclear, 400 kg

Ye-5 Lunar or biter

The Soviets were concerned about proving that their spacecraft had hit the Moon, not recognizing at first that they could be tracked by any other country with the right equipment. Telemetry cessation was not definitive and so the notion was considered of exploding a device on the Moon for all to see, hence the Ye-4 with sufficient payload capacity to carry a nuclear or a large conventional explosive. Korolev was reluctant to use a nuclear explosive, and after consultation with recognized nuclear physicist Yakov Zeldovich and several other physicists this idea was dropped. The Ye-4 itself was eventually abandoned as the technical and political problems became clear, and tracking was recognized as the solution. Even so, the Ye-1 third stage was outfitted with a device to release a sodium cloud for optical tracking and for general observation around the world. The Ye-5 lunar orbiter project was canceled when the new7 8K73 rocket which w7as to launch it suffered engine development problems and was itself canceled.

As the summer of 1958 arrived, Korolev rushed to launch his first lunar impactor before the date set by the Americans for their tiny orbiter. Although he was having technical problems with his first three-stage vehicle, he decided to take the risk and readied his R-7 on the same day as the Americans, but stood down w’hen he learned that the IJS rocket had exploded. But the extra time w as of no avail, and one month later his launch vehicle also exploded after a short flight. Ко matter, the space race was on and its public characteristics were now’ well defined.

In the Soviet program, planning and launch information were held secret and only successful launches reported. Spacecraft that were launched successfully but failed in their objectives had their missions redefined in the Soviet press to make all appear successful. By contrast American plans were announced well in advance, and open to press and public scrutiny. It made for a dramatic contest on each side; one well aware of the other’s plans and proceeding to blind-side its competitor, and the other mostly unaware of the other’s plans and groping almost blindly to seize and retain a leading position.

Six Ye-1/1A spacecraft were launched in the 12-month period between September 1958 and 1959. Only two. Luna 1 and 2. escaped launch vehicle mishaps. Luna 1 and its flight past the Moon wras a sensation to match that of Sputnik almost a year earlier. The Soviet press referred to the w’hole system, launcher and all. as the "First Cosmic Rocket’, and when it passed the Moon the spacecraft was renamed ‘Mechta’ (Dream). Years later, it was retroactively named Luna 1. It w as intended to hit the Moon but on January 4, 1959, it missed its target by about 6,000 km. Nonetheless, it was the first spacecraft to attain Earth escape velocity. On September 14, 1959. the second spacecraft to be launched successfully, Luna 2, became the first spacecraft to impact the Moon, thereby fulfilling Korolev’s program goals for this series.

Ye-1 No 1 Lunar Impact or USSR OKB-1 Luna

Подпись:September 23. 1958 at 09:03:23 UT (Baikonur) Booster failure.

Ye-1 Ко.2 Lunar Impaetor USSR OKB-1 Luna

October 11. 1958 at 23:41:58 UT (Baikonur) Booster failure.

Ye-1 No.3 Lunar Impaetor USSR OKB-1 Luna

December 4, 1958 at 18:18:44 UT (Baikonur) Second stage failure.

Luna 1 (Ye-1 No.4)

Lunar Impaetor USSR OKB-1 Luna

January 2. 1959 at 16:41:21 UT (Baikonur) January 4. 1959

Missed the Moon, entered solar orbit.

Ye-1 A No.5 Lunar Impaetor USSR OKB-1 Luna

June 18, 1959 at 08:08:00 UT (Baikonur) Second stage failure.

Luna 2 (Ye-1 A No.7)

Lunar Impaetor USSR OKB-1 Luna

September 12. 1959 at 06:39:42 UT (Baikonur) September 14, 1959 at 23:02:23 UT Success, impacted Moon.

The scientific goals of these first interplanetary spacecraft were to study cosmic radiation, ioni/cd plasma, magnetic fields and the micromcteoroid flux in the region between the Earth and Moon known as cislunar space. In addition to assisting with
optical tracking, the sodium release experiment would also allow for visualization of the magnetosphere and diffusion in the upper atmosphere of the Earth in transit.

THE YE-6 LUNAR ORBITER SERIES: 1966^1968

Campaign objectives:

OKB-1 started development work on the Ye-7 lunar orbiter at the same time as the Yc-6 soft lander, but it progressed more slowly. After NPO-Lavochkin took over the robotic program the Soviets became anxious to upstage the American orbiter, which was scheduled for its first launch in mid-1966. They also needed to acquire close up imagery of potential landing sites and information on the environment in lunar orbit for the manned lunar program. An incentive presented itself in early 1966 when the long duration manned Voskhod 3 flight that was to have coincided with the opening of the 23rd Congress of the Communist Party in April (the first for new Communist Party leader Leonid Brezhnev) was canceled and there was a requirement for a new’ space spectacular. The Ye-7 was not ready, but Babakin offered to produce a lunar satellite by replacing the lander of the Ye-6 with a pressurized module carrying a payload of readily available instruments. The first orbiter, the Ye-6S, was cobbled together in less than a month. It is possible that the orbiter module was adapted from an Earth satellite of the Cosmos series.

After a launch failure on March 1, 1966, a backup spacecraft was prepared and successfully dispatched to the Moon on March 31, fortunately for Babakin just in time to satisfy the political objective. By becoming the first lunar orbiter, Luna 10 marked another milestone for the Soviet space program. In a moment of theater, it played a recording of the uInternationale’ to the Party Congress.

The US sent its first orbiter to the Moon a little over 4 months later. This project was successful on the first try, and Lunar Orbiter 1 sent back the first pictures from lunar orbit. With landers and or biters returning high quality data, the US was finally catching up.

Spacecraft launched

First spacecraft:

Yc-6S No.204 (Cosmos 111)

Mission Type:

Lunar Orbiter

Country і Builder:

USSR NPO-Lavoehkin

Launch Vehicle:

Molniya-M

Launch Date: Time:

March 1, 1966 at 11:03:49 UT (Baikonur)

Outcome:

Failed to leave Earth orbit.

Second spacecraft:

Luna 10 (Ye-6S No.206)

Mission Type:

Lunar Orbiter

Country j Builder:

IJSSR’ NPO – L avoc h к і n

Launch Vehicle:

Molniya-M

Launch Date; Time:

March 31, 1966 at 10:47:00 UT (Baikonur)

Encounter Date; Thue:

April 3, 1966 at 18:44 UT

Mission End:

May 30, 1966

Outcome:

Success.

Third spacecraft:

Luna 11 (Ye-6LF No. lOl)

Mission type:

Lunar Orbiter

Country і Builder:

USSR, /NPO-Lavochkin

Launch Vehicle:

Molniya-M

Launch Date: Time:

August 24, 1966 at 08:03:00 UT (Baikonur)

Encounter Date і Time:

August 28, 1966 at 21:49 UT

Mission End:

October 1, 1966

Outcome:

Successful orbiter, but no images returned.

Fourth spacecraft:

Luna 12 (Ye-6LF No. 102)

Mission Type:

Lunar Orbiter

Country! Builder:

USSR NPO-Lavochkin

Launch Vehicle:

Molniya-M

Launch Dale ‘: 7 "une:

October 22. 1966 at 08:42:00 UT (Baikonur)

Encounter Date; lime:

October 25. 1966

Mission End:

January 19, 1967

Outcome:

Success.

Fifth spacecraft:

Ye-6LS No. 111 (Cosmos 159)

Mission Type:

Lunar Orbiter Test Mission

Со untry і Builder:

USSR NPO-Lavochkin

Launch Vehicle:

Molniya-M

Launch Dale! 7 "une:

May 16, 1967 at 21:43:57 UT (Baikonur)

Outcome:

Earth orbit test mission, lower orbit than desired.

Sixth spacecraft:

Yc-6LS No. 112

Mission Type:

Lunar Orbiter

Sponsoring Agency:

USSR NPO-Lavochkin

Launch Vehicle:

Molniya-M

Launch Date: Time:

February 7, 1968 at 10:43:54 UT (Baikonur)

Outcome:

Stage 3 failure. Did not reach Earth orbit.

Seventh spacecraft:

Luna 14 (Ye-6LS No.113)

Mission Type:

Lunar Orbiter

Country і Builder:

USSR NPO-Lavochkin

Launch Vehicle:

Molniya-M

Launch Date; Time:

April 7, 1968 at 10:09:32 UT (Baikonur)

Encounter Date/ Tі me:

April 10, 1968 at 19:25 UT

Mission End:

June 24, 1968

Outcome:

Success.

Having achieved lunar orbit ahead of the US and provided the required space spectacular for Moscow, Babakin resumed work on the Ye-7 orbiter whose task was lunar photography. When it was decided to use the Ye-6 cruise stage to make the midcoursc and orbit insertion maneuvers, the orbiter spacecraft became the Yc- 6LF.

Luna 10 had significantly deviated from its predicted path in lunar orbit, and radio tracking had shown the Moon to have an irregular gravity field. As a manned lunar lander would require a precise orbit if it were to land at a preselected point, in

addition to lunar photography the Ye-6LF was given the task of accurately mapping the lunar gravity field.

Two of these spacecraft flew as Luna 11 and 12, and although both achieved lunar orbit an attitude stabilization problem prevented Luna 11 from providing any useful imagery. Even with new tracking data, the navigators could not predict their orbits with the desired accuracy. A second modification to the orbiter module produced the Ye-6LS that was to acquire more precise lunar gravity field data and also test deep space communications for the manned lunar program. After a test mission in Earth orbit and a lunar attempt that was lost to a launch vehicle failure, the third Ye-6LS was successful as Luna 14.

Spacecraft:

These orbiters all used the Ye-6 cruise stage with the lander replaced by an orbiter module. An interesting feature of the orbiters is that they carried no solar panels for recharging batteries, with the result that their operating time was defined by battery life. Lunar orbit insertion was a much smaller burn than the braking maneuver for a landing mission. In the case of the Ye-6S Luna 10, the orbiter module was released on its own in a spin stabilized condition. For the Ye-6LF and Ye-6LS, however, the orbiter modules of Luna 11, 12 and 14 were retained so that they could be stabilized to perform photography. The Ye-6S orbiter module was 1.5 meters long, 0.75 meters in diameter and massed 248.5 kg. It carried two radios transmitting at 18.1 and 922 MHz. Including the cruise stage and a large conical equipment module the Ye-6LF orbiters were 2.7 meters long and 1.5 meters in diameter. The Ye-6LS was similar to the Ye – 6LF but with an improved navigation system to more precisely measure the orbit and apparatus to test a communication system intended for the manned lunar program.

image95

image96

Figure 10.9 Luna 10 Ye-fiS spacecraft (from Robot Explorers): A. Attitude control and radar altimeter; її. Orbiter omni antenna; C. Orbiter module; D. Avionics and communications module; E. Attitude reference sensors; F. Propellant tank; G. Propulsion system; H. Engine nozzle; J. Attitude control jets.

 

image98

Figure 10.10 Luna 10 orbiter module (from Space Travel Encyclopedia)-. 1. Pressurized instrument module; 2. Radiometer; 3. Magnetometer; 4. Antennas.

 

image97

image99

Figure 10.11 Luna 11 and 12 Ye-6LF spacecraft: 1. Helium tanks for attitude control pressurization; 2. Imaging system; 3. Thermal control radiator; 4. Radiometer; 5. Instrument module; 6. Battery; 7. Attitude control sensors; 8. Omnidirectional antenna; 9. Attitude control avionics; 10. Attitude control engines; 11. Main engine; 12. Propellant tanks.

 

Подпись: 1,584 kg (orbiler module 248.5 kg) 1,640 kg 1,620 kg 1,700 kgLuna 10 launch mass: Luna 11 launch mass: Luna 12 launch mass: Luna 14 launch mass:

Payload:

Ye-6S Luna 10:

1. Boom-mounted triaxial fluxgate magnetometer

2. Low energy x-ray spectrometer

3. Gamma-ray spectrometer

4. Gas discharge counters

5. Ion trap solar plasma detectors

6. SL-1 radiometer

7. Micrometeoroid detector

8. Infrared radiometer

9. Gravitational field mapping experiment (using spacecraft tracking)

The Yc-6S flown as Luna 10 had seven instruments developed for the Ye-7, but not the camera. The magnetometer was on a 1.5 meter long boom. Low energy x-ray and gamma-ray spectrometers were to measure the composition of the lunar surface; piezoelectric sensors were to measure micrometeoroid fluxes; an infrared radiometer was to measure thermal radiation from and the temperature of the lunar surface; gas discharge counters were to measure solar and cosmic rays in the lunar environment and soft electrons in a lunar ionosphere; ion traps were to measure electrons and ions in the solar wind and search for a lunar ionosphere; and the SL-1 radiometer was to measure the lunar radiation environment. Another key investigation was to measure the lunar gravity field by radio tracking of the spacecraft. There was no imaging on this first hastily prepared orbiter.

Ye-6LF Luna 11 and 12:

1. Facsimile imaging system

2. Low energy x-ray spectrometer

3. Gamma-ray spectrometer

4. SL-1 radiometer

5. Micrometeoroid detectors

6. Ultraviolet spectrometer

7. Long-wave radio astronomy experiment

8. Gravitational field mapping experiment (using spacecraft tracking)

9. Lunar rover wheel drive technology experiments

The imaging system was similar to the facsimile film camera used by Zond 3 the previous year. At the altitude at which the pictures were to be shot, an image would encompass an area of 25 square kilometers and the 1,100 scan lines would provide a maximum surface resolution of 15 to 20 meters. Two cameras were carried on each mission. The ultraviolet reflectance spectrometer was to measure the structure of the surface. Ко data was ever published on the composition of the lunar surface or of the magnetic field, radiation and micrometeoroids in the lunar environment. Nor was the analysis of the irregular gravity field published. In addition to scientific instruments, the spacecraft carried technology tests of lubricants for operating gears and bearings in vacuum to qualify them for use on lunar rovers.

Ye-6LS Luna 14:

1. Lunar communications system test

2. Cosmic ray detector

3. Solar wind plasma sensors

4. Radiation dosimeter

5. Gravitational field mapping experiment (using spacecraft tracking)

6. Lunar rover wheel drive technology experiment

The main goal of Luna 14 was to test the spaceborne and ground segments of the new communication system for the manned lunar program. Other objectives were to continue to investigate the lunar radiation and plasma environment and to use a new: navigation system to more precisely map the lunar gravity field and librations. The spacecraft also carried more engineering tests of lunar rover motors including gears, ball bearings and lubricants Гог vacuum operation.

Mission description:

On March L 1966, the first spacecraft, Yc-6S No.204. was stranded in parking orbit when the fourth stage lost roll control during the unpowered coast and was unable to lire its engine for the escape burn. It was designated Cosmos 111 and re-entered the atmosphere 2 days later.

Four weeks later on March 31,1966. Ye-6S No.206 was successfully dispatched as Luna 10. It made a mideourse correction the following day and then at 18:44 IJT on April 3 it became the first spacecraft to enter orbit around another celestial body, achieving a 350 x 1,017 km orbit inclined at 72 degrees to the lunar equator with a period of 2 hours 58 minutes. The cruise stage then released the or biter module. On April 4 the ‘Internationale was played to the 23rd Congress of the Communist Party of the Soviet Union. In Tact w hat the Congress heard was a rehearsal playback from the previous evening, because at a second rehearsal on the morning of the meeting it w as observed that one of the notes had gone missing. Luna 10 operated for 56 days. 460 lunar orbits and 219 radio transmissions before the battery drained and contact was lost on May 30, 1966.

Spacecraft Ye-6LF No. 101 was launched on August 24, 1966, as Luna 11, and at 21:49 UT on August 28 it entered a 160 x 1,193 km lunar orbit that was inclined at 27 degrees with a period of 3 hours. Coming 2 weeks after the first US or biter, there was every expectation in the West that the Soviet mission would send back images. The transmissions had been recoded to prevent interception by the likes of Jodrell Bank, but no pictures w’ere forthcoming. An attitude control thruster had failed and prevented aiming either the camera or the ultraviolet instrument at the lunar surface. It was suspected that something had become lodged in the nozzle of the thruster. By sheer bad luck, the x-ray and gamma-ray spectrometers also failed. The spacecraft w as placed into a spin stabilized mode and the other experiments apparently worked satisfactorily. After 38 days, 277 orbits and 137 radio transmissions the batteries ran out on October 1, 1966, and the Soviets, without mentioning imaging, reported that the mission was complete.

Ye-6LF No. 102. Luna 12. entered a 3 hour 25 minute 103 x 1,742 km lunar orbit inclined by 36.6 degrees on October 25, 1966. It did not suffer the problems of its predecessor except for the ultraviolet spectrometer, which again failed. Tile primary objectives were the lunar photography that Luna 11 had been unable to provide and to continue to chart the gravitational field. On October 29 the spacecraft transmitted its first photographs. In this regard the Soviets were 2 months behind the Amerieans. A total of 40 images were returned by each of the two cameras. Once the spacecraft had finished imaging, it was placed into a spin stabilized mode and the other tasks were sueeessfully performed, ineluding testing electric motors for a rover, hven with the new gravity maps developed by tracking Luna 1L the orbit of Luna 12 deviated surprisingly far from that predicted. Its perilune dropped by 3 to 4 km, day relative to the prediction, and the failure of one of the attitude control thrusters made it difficult to raise the perilune to compensate. Finally, on January 19, 1967. after 85 days. 602 orbits and 302 communication sessions, transmissions ceased.

The next mission to be launched was a test flight of the second modification to the orbiter. The Ye-6LS No. lll spacecraft was to be launched into a highly elliptical Earth orbit with an apogee near 250.000 km in order to perfect a means of accurately measuring and adjusting an orbital trajectory to compensate for gravity anomalies, but the fourth stage shut down prematurely leaving the spacecraft in a lower 260 x 60,710 km orbit. Despite the low apogee, it was probably put through its intended operations. Designated Cosmos 159, it re-entered on November 11, 1967. The Ye – 6LS No. l 12 spacecraft failed to achieve parking orbit when the third stage ran out of propellant early at the 524 second mark as a result of excessive fuel consumption through the turbine gas generator. The last spacecraft of this type. Yc-6LS No. l 13. was successfully dispatched as Luna 14 and at 19:25 UT on April 10. 1968. it entered a 160 x 870 km lunar orbit at 42 degrees. It marked the end of the second generation of Luna missions.

Results:

Luna 10 conducted an extensive study of the Moon from lunar orbit. Its path varied much more than the Soviets expected. This was due to a very uneven gravity field that featured localized ‘mass concentrations’ (mascons) below the surface. Luna 10 established the importance of charting the lunar gravity field, and also of providing spacecraft with robust propulsion for precise control of their orbital trajectories. The Soviets discovered this well before the Americans, who were generally given credit because their space program results were more widely published. Luna 10 found the Moon to have no detectable atmosphere, the lunar surface to have large expanses of basalt but few, if any. granitic provinces, and measured the amount of potassium, uranium, and thorium in the crust. It mapped a magnetic field whose strength was 0.001 % of Earth, and found it not likely to be intrinsic. It showed that the Moon had no trapped radiation belts like those of Earth. The micrometeoroid flux and cosmic radiation in lunar orbit was also measured.

The x-ray and gamma-ray spectrometers on Luna 11 failed and imaging was not possible, but it was able to make observations of solar radiation and also conducted a successful test of lunar rover reduction gear operation in vacuum. The first images

image100

Figure 10.12 Luna 12 image taken from 250 km of an area of 25 square kilometers south of the crater Aristarchus.

were obtained by Luna 12. On October 29, 1966, it transmitted images of the Sea of Rains and the crater Aristarchus with resolution of 15 to 20 meters. Owing to their low quality, only the first few images were released. Ironically, the Soviets used the more extensive and far better imagery from the Lunar Orbitcr scries to select landing sites. Furthermore, like the Americans they ultimately chose three sites, one each in the Sea of Tranquility, the Central Bay and the Ocean of Storms. The radio tracking of Luna 11 and 12 revealed the need for even better orbital tracking experiments to provide a more precise lunar gravity map. Luna 12 also detected x-ray fluorescence of the surface induced by the solar wind, and this provided a means of measuring ihe composition of the surface. Radiation fields and micrometeoroid flux were measured in lunar space and the engineering test of reduction gears was successful.

The mission of Luna 14 passed almost without comment, perhaps because to have described what it was doing would have revealed too much about the manned lunar program. It was assumed in the West at the time to be a failed photographic mission, but it is now known to have mapped the figure of the Moon and its gravity field to a high degree of precision, to have provided data on the propagation and stability of radio communications to the spacecraft at different orbital positions, measured solar wind plasma and cosmic rays in lunar orbit, measured the librational motion of the Moon, and determined the Harih-Moon mass ratio. The eommunicalions system for the manned lunar program was also successfully tested. Further engineering tests of rover motors were conducted to select the materials and lubricants that operated best in vacuum for the systems intended for roving vehicles.

ПІЕ YE-8 LUNAR ORBITER SERIES: 1971-1974

Campaign objectives:

In addition to the lunar surface rover and sample return missions, the Ye-8 modular spacecraft also flew orbital missions to support the engineering requirements of the planned manned missions. The principal requirements were to photograph the lunar surface at high resolution and conduct remote surface composition measurements to assist in selecting landing sites. Л secondary objective was to acquire data on the radiation and plasma in lunar orbit in order to understand the risks to humans. Two Ye-8LS orbiters were launched successfully as Luna 19 and 22. Their tracking data continued the accurate mapping of the lunar gravity field that Luna 14 initiated.

Spacecraft launched

First spacecraft:

Luna 19 (Ye-8LS No.202)

Mission Type:

Lunar Orbiter

Country і Builder:

USSR, NPO-Lavochkin

Launch Vehicle:

Proton-K

launch Date ‘: 7 Ъпе:

September 28. 1971 at 10:00:22UT (Baikonur)

Encounter Date; Tinie :

October 3, 1971

Mission End:

October 3, 1972

Outcome:

Success.

Second spacecraft:

Luna 22 (Ye-8LS No.206)

Mission Type:

Lunar Orbiter

Country! Builder:

USSR, NPO-Lavochkin

Launch Vehicle:

Proton-K

Launch Date ‘: 1 Ъпе:

May 29, 1974 at 08:56:51 UT (Baikonur)

Encounter Date:Tinie:

June 2, 1974

Mission End:

November 1975

Outcome:

Success.

Spacecraft:

The spacecraft was essentially the same as the lander stage for the lunar rover, but with a payload consisting of a pressurized module for the orbital instruments. This was a squat cylinder and, just like the Lunokhod, had a hinged lid that exposed solar panels on the underside.

image166

Figure 12.20 Luna 19 spacecraft.

Luna 19 launch mass: 5,700 kg

Luna 22 launch mass: 5,700 kg

Payload:

1. Imaging system

2. Gravitational field, experiment

3. Gamma-ray spectrometer for surface composition

4. Radiation sensors

5. Magnetometer

6. Micrometeoroid detector

7. Altimeter

8. Radio occultation experiment

For these arbiters, new linear-scan cameras were developed based on the Luna 9 and 13 panoramic imagers. Basically the motion of the spacecraft provided the long axis of the image and the photometer scanned only perpendicular to the direction of orbital motion. The field of view was 180 degrees centered on the nadir and gave a ‘cylindrical fish-eye’ image. At 4 lines per second from an altitude of 100 km it had a resolution of 100 meters in the direction of travel and 400 meters perpendicular to it. Luna 22 carried an additional camera and engineering tests of solid lubricants for operation in vacuum and wafer tests of surface reflection properties.

The Ye-8 lunar orbiter series: 1971-1974 265

Mission description:

Luna 19 was launched on September 28, 1971, and on October 3 it entered a 2 hour circular lunar orbit at 140 km inclined by 41 degrees. Three days later the orbit was changed to an elliptical one of 127 x 385 km. Several months later the perilune was lowered to 77 km to undertake closer photography. After more than 4,000 orbits the spacecraft ceased operations on October 3, 1972.

Luna 22 was launched on May 29, 1974, and entered a 219 x 221 km lunar orbit at an inclination of 19.6 degrees on June 2. It made many orbit adjustments over its 18 month lifetime to optimize experiment operation, at times lowering its perilune to 25 km to improve photography. Sporadic contact was maintained after the supply of attitude control gas ran out on September 2, and the mission was concluded in early November 1974.

image167

Figure 12,21 Section of a panoramic image from Luna 19 of Sinus Aestuum with the crater Eratosthenes at the right.

image168

Figure 12.22 Luna 22 panorama fragment illustrating the ‘cylindrical fish-eye’ effect of the linear scanning photometer imager.

Results:

Luna 19 and 22 both returned images of the lunar surface from orbit, with Luna 19 apparently returning about 5 panoramas and Luna 22 ten panoramas. Both spacecraft extended the systematic study to locate mass concentrations (mascons) begun by the earlier Luna orbiters. They also remotely sensed the composition of the surface and directly measured the properties of the orbital environment including the radiation, plasma, magnetic fields and micrometeoroid flux. Altimetry measure­ments of lunar topography were made, and the electromagnetic properties of the regolith examined. The results must have been substantial but few results were published, particularly from Luna 22.