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Before flying off into the expanses of space, Zond-3 photographed the far side of the Moon. Photographing and transmitting the pictures to Earth was done with a new, smallsize photo-TV system designed for operation in the conditions of lengthy flight.

Photographs were taken from a distance of approximately 10,000 kilometres, the operation requiring somewhat more than an hour. The distance at which the photographs were taken was optimal for covering a considerable part of the lunar surface and obtaining photographs of sufficiently large scale.

The 25 photographs taken were transmitted by television with 1,100-line scanning, instead of the 625-line scanning of the conventional TV set. It required 34 minutes to transmit each frame. The photo-TV set is designed for transmitting pictures of the planets from distances of hundreds of millions of kilometres. During this flight, however, the apparatus will not photograph the planets but. will repeat the transmission of the lunar photographs from great distances. The launching time selected precludes the possibility of Zond-3 nearing any planet. But there can be no doubt that the experience gained through the flight of Zond-3 will be made use of in subsequent launchings for photographing distant planets.

2. The Purpose of the Proton Satellites

The satellites of the Proton series weigh 12.2 tons — the heaviest in the world launched by the beginning of 1967. Proton-1 was put into orbit on July 16, 1965; Proton-2 on November 2, 1965; and Proton-3 in June 1966. A new carrier rocket was used -which( developed a thrust of 60 million horsepower, three times the power of the rocket which put into orbit Vostok-1 with Yuri Gagarin on board.

to discoveries which reveal the immense diversity of the elementary particles composing the matter of the universe.

In order to penetrate further into the innermost depths of elementary particles physicists must have particles of higher and higher energy. But when primary cosmic rays of high and ultrahigh energy enter the atmosphere they collide with the nuclei of its atoms, and it is only secondary cosmic rays, the product of these collisions, which reach the Earth’s surface. Consequently it is practically impossible to study primary cosmic rays in terrestrial conditions. Physicists, it is true, have found a partial

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3 . S c ie n tific O b ser v a tio n s by th e K osm os S a te llite s

The artificial satellites of the Kosmos series are often referred to as toilers of space science. And indeed they form the most numerous subdivision of Soviet spacecraft. In the period between March 1962 and June 1974 the Soviet Union orbited 660 Kosmos satellites. In the recent period every year sees about seventy research vehicles being orbited in near space.

The research programme of the Kosmos satellites is extensive. It includes such objects of study as the Earth, its atmosphere, near space, corpuscular fluxes and cosmic rays. These satellites are being used for the study of many problems of space medicine and biology and for the solution of many problems bearing on the design and manufacture of space vehicles.

The Kosmos satellites are orbited from several different launch

thousands of kilometres. To carry out the extensive programme of the Kosmos satellites several different types of launch vehicles with payloads ranging from several hundred kilogrammes to several tons are used. A two-stage rocket thirty metres long and 1,65 metres in diameter has been extensively used for launching

and hydrocarbon fuel. The second stage is fitted with an RD-119 engine developing a thrust of M tons and using liquid oxygen and unsymmetrical dimethylhydrazine as a fuel. The artificial satellite is located under the nose cone of the rocket. It is separated from the final stage after being put into orbit.

The manufacture of a large number of Kosmos satellites made it necessary to develop a standardized design, systems and instruments. The body is a cylinder with spherical end plates. It is divided into compartments to house power supply sources, on-board equipment and scientific instruments atid apparatus. Depending on the purpose of the satellite solar cell batteries, sensors of instruments and aerials are fitted outside the body.

The standardized satellites are fitted with a small-sized complex of systems which includes a radiotelemetry system with a memory, radio command link and other instruments.

Some of the Kosmos satellites are fitted with descent modules to return scientific equipment, research objects and materials to the Earth.

The Kosmos satellites are often used for the development and optimization of systems and equipment for spacecraft which will subsequently be used for purposes of research or for the national economy. Thus, the equipment for weather observations was first tested on the Kosmos-122. This equipment was improved and

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orientation system takes over. Rotating masses controlled by solar sensor signals are used in the process.

After the divergence angles and angular speeds have been decreased to a certain limit, settled conditions prevail. By settled conditions is meant the maintenance of the oriented axis in the direction of the Sun, and practically this means small-amplitude oscillations of this axis about a preset direction with a certain accuracy.

Earth orientation is needed for investigating the Earth’s radiation Conditions and its atmosphere, the energy distribution in the Earth’s thermal radiation spectrum and some other

However, aerodynamic stabilizers alone cannot dampen oscillations, and therefore, the stabilization system is supplemented by a special damping device.

A preliminary damping system is installed to eliminate disturbances originating when the satellite is separated from .the carrier rocket.

5. The Prognoz Investigates the Sun

At presfent the Sun is being studied with the aid of different space vehicles, namely automatic Earth satellites, manned spaceships and orbital stations, lunar and interplanetary probes. Among the automatic research vehicles engaged in the investigation of the Sun the Prognoz artificial earth satellite occupies a special place.

While circuiting the Earth in such a remote orbit the Prognoz measures solar wind, the characteristics of solar roentgen, gamma-ray and radio emissions. These measurements are made while the satellite is outside the Earth’s magnetosphere.

Together with the findings of Earth-based observatories conducting continuous observation of the Sun, the magnetic field of the Earth and cosmic rays, this information helps the scientists study the mechanism of solar activity, to get a more authentic idea about the Sun-Earth interrelationships and ultimately create the foundations for space weather forecasts.

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As far as design is concerned the automatic space station Prognoz is a pressurized cylindrical container with spherical end plates. Inside the container there are several platforms on which research instruments, the apparatus of the telemetry complex, the elements of the sun-seeker attitude control system, power supply and temperature control systems are installed. The pressurized container is filled with inert gas.

The sensors and units of scientific apparatus, the micromotors of the attitude control system, the radio complex aerials and telemetry equipment are mounted on the external surface of the

While the satellite is in flight, scientific data and data on the work of the on-board systems are recorded in the memory. During the radio communication sessions all these data are quickly transmitted to the Earth.

The scientific instruments of the Prognoz have been combined into separate groups in keeping with the phenomena studied. The first group comprises the instruments for measuring solar electromagnetic radiation when solar flares occur, including an X-ray spectrometer to register the radiation in the region of 1.5—30 thousand electron-volts and gamma-ray scintillation spectrometer to register radiations in the energy region of 30— 350 thousand electron-volts.

Another group of instruments measures the solar cosmic ray

a magnetometer and instruments for attitude control registration.

200,000 kilometres, returning to it to a distance of 950 kilometres.

During each circuit of the planet, which lasted 96 hours, the instruments of the station measured the characteristics of the solar wind and cosmic rays in varying physical conditions. At the maximum distance from the Earth the motion of the solar particles was free. As the solar wind flowed round the magnetosphere at a distance of 80,000 kilometres a distinctive

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transition zone of the magnetosphere was investigated. In near space the instruments of the station supplied information on the effect of solar radiation on the Earth’s radiation belt.

In June 1972 another station— the Prognoz-2 — was launched. In addition to a complex of Soviet-made equipment, the Prognoz-2 carried scientific instruments manufactured by French specialists. This joint experiment was conducted in keeping with a programme of Soviet-French cooperation in space research and exploration. The French equipment helped extend the scope of investigations of the characteristics of the outer magnetosphere and solar gamma-ray radiation. They were also used for measuring neutron fluxes from the Sun.

possible to obtain a wealth of factual material on solar radiation and its effect on the magnetosphere of the Earth. The experience accumulated in the work with the Prognoz stations displayed the high effect of the investigations of the Sun achieved with the aid of such vehicles. That was why in February 1973 another such station — the Prognoz-3 — was launched into space.

The Prognoz satellite system is a heiiophysical complex designed to keep constant watch in outer space. The Prognoz stations have been actively studying the Sun, the Sun-Earth interrelationships and near space.

6. The Molnia Relay Satellite

Progress made in space technology has opened another possibility for transmission of information over vast distances, namely through artificial Earth satellites. A communication satellite put into an orbit with an apogee of 35-40,000 kilometres will “see” and irradiate one-third of the Earth’s surface. The employment of a satellite communication system is both important ana commercially advantageous for the USSR which has a vast territory with countless natural barriers and regions in the Far North, Siberia and the Far East to which access is difficult.

To this end a communication satellite — the Molnia-I — has been developed with a system of ground based receiver stations known as the Orbita.

The Molnia-1 which was the first Soviet communication satellite was launched on April 23, 1965. It opened regular operation of space vehicles for radio and TV communication.

The Molnia-1 was put into a high-altitude elliptical orbit with the apogee in the North Hemisphere, the maximum altitude being about 40,000 kilometres. The satellite makes one complete circuit every twelve hours. Thanks to the choice of such an orbit the entire territory of the Soviet Union remains in the field oi view

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As far as design features are concerned the Molnia-1 communication satellite comprises a cylindrical container with tapered ends. Six solar-cell battery panels and two pencil beam parabolic reflector aerials have been fitted to the body. In the bottom of the body there are attitude control sensors for orientation on the Earth and the Sun.

To ensure, synchronous flight it is necessary to provide exact timing of the semi-diurnal circuiting period in orbit. To this end the Molnia-1 has been fitted with a vernier engine installation which executes regular orbital correction.

The radioelectronic devices are arranged inside the pressurized body of the satellite in which constant temperature and pressure conditions are maintained.

7. The Proton Space Station Design

The Proton space station is essentially a complex automatic scientific laboratory.

The internal sealed body of the Proton station protects it against aerodynamic forces and temperature effects while it is being put in orbit. To prevent excessive heating and cooling in orbital flight, the body of the station is coated externally with, highly effective, thermal insulator. Inside the sealed body the required temperature and normal pressure are maintained.

The sealed body of the station is a cylinder with a convex bottom. Inside the cylinder, in the rear and central sections research instrumentation and auxiliary systerps are packed.

Solar cell banks, a mechanism for opening them and sensors of the station position-indication system are . installed outside. Active damping electric-pneumatic systems with compressed gas cylinders, gas nozzles and'controlling equipment are installed on the rear butt-end, along with an external radiation heat exchanger. The antennas of the telemetric system, radiocommand set and trajectory-measurement set are located on the body. Between the outer constructional shell and the body proper there are containers with chemical cells.

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Reliable and accurate measurements of orbital parameters are ensured ‘by ground measuring sets and an on-board signal radiosystem.

Operation of research instrumentation and all systems aboard is controlled by both on-board programme-time devices and by radiocommands from the Earth.

The possibility of determining the position of the station in space at each moment enables the investigators to register the direction of cosmic rays under study.

respect to all three axis, a damping system is provided, including gas nozzles, high-pressure cylinders and control equipment. The station’s slow rotation is necessary to ensure normal, operation of the solar cells and more uniform temperature conditions,. Besides, all directions of motion of cosmic-ray particles can be scanned by measurements owing to this rotation.

To ensure temperature conditions necessary for the normal operation of equipment, the station is fitted out with a thermal control system.

The solar cells energize the instrumentation on the illuminated side of the orbit and charge a standby chemical cell for power supply on the shaded side of the orbit, i. e., when the station is

re-entry capsule is 2.4 tons, and its diameter 2.3 meters. The pilot wearing a space-suit is seated in an ejectable chair; the ship is controlled either automatically or manually by the cosmonaut. The life-support system is designed to function for ten days; radio contact with ground-based facilities is maintained continuously. To land the ship, the retroengine is switched on to decelerate the ship and put it into a descent path; then the re-entry capsule is separated and after its atmospheric deceleration the cosmonaut is ejected at an altitude of 7 kilometers and brought to the ground by parachute,

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The Voskhod multiseater spaceship differs from the Vostok spaceship both in design and equipment; it has a soft-landing system, a standby retroengine, ana additional instrumentation (an extra attitude-control system with ionic sensors, advanced

rocket was meant for peaceful use. The two-stage rocket powered

consists of four lateral units, 19 meters long and 3 meters in diameter, each unit being provided with the RD-107 engine; the central unit (second stage) is 28 meters long and 2.95 meters in diameter, and provided with the RD-108 engine; the third stage is 10 meters long and 2.58 meters in diameter, and it is provided with a single chamber rocket engine with four rudder nozzles. The six-engine propulsion system of the rocket attains a total thrust of 600 tons and a maximum useful power in flight of 20 million h. p. Advanced rocket .engines and rocket design features are decisive factors making possible a space flight. The rocket

The specific impulse of rocket engine is the main characteristic of its efficiency. The specific impulse of the RD-107 engine powering the first stage of the Vostok carrier-rocket (in operation since i957) exceeds by almost 30 units that of the advanced US engines (H-l) of the same thrust (also using oxygen and kerosene) which has powered the first stage of Saturn IB rocket since 1966.

The specific impulse of the RD-107 engine in a vacuum is 314 seconds; its thrust is 102 tons. The swinging rudder chambers fed from the general turbopump unit reduce the specific impulse by a mere second. The rocket engines developed in the USSR in subsequent years have considerably superior characteristics. The high specific impulse of the engines installed ip Soviet carrierrockets permitted the use of vast power with a moderate fuel consumption.

The development of such engines was one of the outstanding achievements that made possible Soviet successes in space exploration. Perfect engine designs, control systems and

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