Geodesy and Mapping Through 1980

Prior to 1957, geodesy, the study of the shape and size of the Earth and the determination of geocentric coordinates of points on its surface, was dependent only on ground measurements over small areas limited by the borders of states and continents. It was mainly due to this that there were discrepancies between geodetic networks determined in different parts of the globe and relatively large degrees of uncertainty in the connection between different continents. The availability of artificial satellites as objects for geo­detic measurements greatly increased the scope of geodesy and sat­ellite geodesy is now an important applied science. Satellite geode­ sy is being successfully applied to the studies of geodynamics, prac­tical and theoretical geodesy, and geophysics. To solve most of the problems, in addition to improvements in equipment and observa­ tional techniques, effective scientific cooperation, unification of processing methods, continuing information exchange, and rational distribution of labor between participants are necessary. Interna­ tional cooperation started soon after the first techniques of satellite geodesy were developed, first on the basis of bilateral agreements and regional programs, and afterwards within the framework of the International Committee on Space Research [COSPAR]. The Soviet Union works through the Interkosrnos program and certain developing countries, including Mozambique, Angola, Seychelles, Mali, India, and Egypt. In 1981, the Interkosrnos network included 25 photographic and 12 laser-ranging stations (10-7 in Europe, 6-1 in Asia, 6-1 in Africa, and 3-3 in South America). The geometric method of space triangulation—the simultaneous observation of a satellite from two or more stations—provides a simple technique for developing basic geodetic networks for mapping unsurveyed ter­ ritories and for developing natural resources comparatively quickly and inexpensively. 231

The Soviet Union's National Paper to the Second United Nations Conference on the Exploration and Peaceful Uses of Outer Space devotes a complete section to the utilization of satellite tracking data for geodetic and geophysical problems in the interests of de­veloping countries. It reports that, from 1970 to 1980, as part of international programs of satellite tracking, more than 98,000 posi­tions of satellites have been photographed and 66,000 laser-ranging distance measurements have been made. As a result of this the di­ rections and coordinates of the European and North African parts of the network have been reduced to a single reference system to within 10-20 meters. 232

Besides triangulation methods it has become possible to deter­mine a position on the Earth's surface using the Doppler naviga­ tional satellite system described earlier in this chapter. By comput er-processing the results of some 20 or more determinations made in a 2 or 3 day period it is possible to establish a fixed position to within 1 or 2 meters. It might be noted that Western experts at a recent conference were talking in terms of decimeter accuracy by such techniques before long. 233 Such precision is necessary for lo­ cating caps of oil wells beneath the surface of the sea and defining interstate borders at sea. Most satellite observatories operating within the Interkosmos program are equipped with the Doppler in­ stallations and carry out regular observations as part of the inter­ national programs.

As reported in the previous section of this chapter, the Priroda Center is part of the Chief Administration of Geodesy and Cartog­ raphy of the Council of Minister of the U.S.S.R. An article by LA. Kutuzov, of the administration, and Yu. P. Kiyenko, of the Priroda Center, describes space cartography in the U.S.S.R. The following quotations are taken from the abstract of their article.

Space surveys of the Earth have significant advantages over other methods for obtaining information for map compilation. The most important of these advantages is the areal coverage of space images. >From satellites of the "Meteor" type the width of the surveyed zone is thousands of kilometers, whereas from stations of the "Salyut" type the photographed zone has a width of 450 km. In a short time an enormous area can be pho­ tographed; for example, in 5 minutes a survey of a million square kilometers can be made from an orbital station. Due to the high position of the center of projection, the central projec­ tion in which the image is constructed becomes close to orthog­ onal and this makes it possible to simplify a number of proc­esses in photogrammetric work in map production. . . . The in­ accessibility of areas has lost its importance and remote, un­ populated areas can now be surveyed safely, quickly and inex­pensively without the organization of time-consuming, arduous expeditions, in the U.S.S.R., such areas include the Pamir and Tien Shan, Chukotka and Novaya Zemlya, the Kurile Islands and deserts of Central Asia. 234

geodetic kosmos flights with the C-l

With the exception of a few flights, such as Interkosmos 10, and general references to "Meteor" and "Salyut" types the Russians have not identified geodetic or mapping flights specifically. This study, therefore, must limit itself to inferential candidate flights for these purposes and presumably these are buried within the Kosmos series. Such candidates would be those with near-circular orbits with sufficiently high periods to ensure mutual visibility be­ tween stations separated by large distances for a reasonable dura­ tion so that multiple observations can be made. Table 41 lists C-l launched Kosmos payloads with such orbits. With two exceptions these will be seen to fly somewhat higher than the contemporary navigation satellites which have periods close to 105 minutes in near-circular orbits at approximately 1,000 km above the Earth's surface. The satellites with 74° inclination fall into two categories; those with periods close to 113 minutes at approximately 1,400 km, and those with periods close to 109 minutes at approximately 1,200 km. Flights at 83° show no such dichotomy being all at approxi­ mately 1,200 km. The two exceptions, Kosmos 842 and 911 had pa­ rameters indistinguishable from those of navigation satellites but Kettering Group analysis based on orbital-plane spacing, lack of signals on 150 MHz and no obvious gaps in the series of identity numbers at the relevant times, make the net balance of evidence that they are more likely geodetic rather than navigation flights.

possible mapping missions within the photo reconnaissance flights

A special subset of recoverable Kosmos satellites, transmitting the two-tone tracking beacon on 19.994 MHz, instead of the usual 19.989 MHz, exists within the third generation missions. These do not maneuver and have a TL recovery beacon instead of the usual TFs or TKs. The nonmaneuvering feature led to their initially being classified as successors to the first-generation low resolution flights. As time passed and such flights appeared, in general, only two or three times a year at times close to the equinoxes and at different annual inclinations to the Equator, some other role was sought and it is now thought that they perform a geodetic survey and mapping function. With the Sun overhead close to the Equa­ tor, there will be average illumination in both Northern and South­ern Hemispheres. 235

The Soviet Union has the need to be able to correlate the inter­national mapping grids for precise targeting of its missiles with MIRVed warheads and it has been suggested that this is achieved by taking simultaneous photographs in opposite directions of ground targets and star backgrounds using laser technology. 236

kosmos 1045

This satellite is also included in table 39 on the grounds that, al­ though distinctly different from all others in the table, having been launched by the F-2 instead of the C-l, its orbital parameters put it closer to the geodetic subset than to any other recognized group­ing. Even so, it is higher than any of those having a period close to 120 minutes at approximately 1,700 km. Its mass has been estimat­ ed as a possible 3,400 kilograms which, with the two amateur radio satellites launched with it, each of mass 40 kg, is well within the capability of the F-2 at that height and the 82.5° inclination.

SPACE MANUFACTURING

In 1978, a popular book with the title "Industry in Space" was published in Moscow. Among the chapter titles are "Foundry above the Earth," "Other materials which did not exist before," and "Bi­ology and pharmacology in space." The book highlighted the prob­lems of using the conditions of high vacuum and microgravity and considered various uses such as obtaining materials with unusual physical-mechanical properties, large single crystals, and super-pure materials, including medicines. 237

In a Pravda article published in 1980, cosmonaut Valeriy Kuba- sov defined space technology as encompassing a set of technological processes conducted in orbit utilizing the physical factors of outer space—primarily weightlessness 238 and vacuum. He named the two most important areas of space technology as the repair and as­sembly of equipment in near-Earth space and the production of ma­ terials and articles with new or greatly improved properties. 239

soyuz 6

Launched on October 11, 1969, as the first in the "troika" mis­ sion, this flight was commanded by Lt. Col. Georgiy Shonin with Kubasov as his flight engineer. It carried, in the orbital module, a specialized research unit, "Vulkan," developed at the Ukrainian S.S.R. Academy of Sciences' Electric Welding Institute, to investi­ gate alternative methods for welding in conditions of high vacuum and microgravity. The Vulkan unit was remotely controlled by electric cable from the command module after the communicating hatch had been sealed and the orbital module depressurized and opened to the high vacuum conditions of space. Three methods were tested:

• A low pressure compressed arc,
• An electron beam, and
• Arc welding with a consumable electrode.

Only the electron beam experiment was reported as completely successful in initial accounts. However, more recently, Kubasov claimed that, on October 16, the final day of the mission, metals were cut and welded by several methods. He comments that at the time it was difficult to evaluate the entire significance of the ex­ periments without some hesitation but that they can now be seen as impetus to the practical development of space technology. They demonstrated the possibility of manipulating molten metal under conditions of microgravity and high vacuum. It had been possible to ensure the directional transfer of molten metal into the welding bath, form a weld seam, and localize the crystallizing metal along the edges of the cut exactly as is done on Earth. He also points out the psychological importance of successfully demonstrating the ability to cope safely with molten metal, sparks, and high voltages on board the spacecraft. 240 The article concludes with discussion of related experiments conducted on board Skylab in 1973, during the joint Apollo-Soyuz mission of 1975, when Kubasov was a member of the two-man Soyuz crew, and in Salyut orbital stations.

the apollo-soyuz test project

The ASTP experiments package comprised 28 separate experi­ ments. Five of these were joint U.S.-U.S.S.R. experiments. One of 18 approved on August 16, 1973, was MA-010, the multipurpose electric furnace with A. Boese, of the Marshall Space Flight Center, as principal investigator. Based upon a similar furnace (M-518) flown on Skylab, this furnace was used to heat and cool mate­ rial samples in space, thereby taking advantage of the lack of ther­ mal convection and sedimentation during the liquid or gaseous phase of the material being processed. Seven experiments were per­ formed. The guiding design requirement for the multipurpose elec­ tric furnace system was to produce an apparatus that provided the widest possible flexibility in applying predetermined temperature distributions and temperature/time sequences within the con­ straints imposed by existing interfaces. Although the Skylab multi­ purpose furnace met all expectations of performance and reliabil­ ity, it was apparent that improvement in function could be ob­ tained with some specific modifications for ASTP. The system con­ sisted of three essential parts:

1. The furnace,

2. A programmable electronic temperature controller that
provided the desired temperatures, and

3. A helium rapid cooldown system. 241

Joint experiment MA-150 was designed by the Soviet Principal Investigator, I. Ivanov, and used the American MA-010 furnace in the docking module. There were three identical cartridges, each containing three ampules, and all three cartridges were returned to the Soviet Union on Soyuz. One ampule contained aluminum powder that was melted (at 700 °C) in an attempt to produce per­fect spheres when the melt cooled. Spheres were produced, but alu­ minum oxide influenced their formation and they were not perfect; they were about the same as spheres produced in 1-g.

During the first 3 hours after the furnace was switched on, the temperature rose linearly from 0 °C to 1150 °C. This temperature was maintained for 1 hour and was then reduced in an active cool­ ing phase at a rate of 0.6 K/min for nearly 4 hours. For the re­mainder of the 10-hour duration of the experiment, the tempera­ ture fell with passive cooling, following the switch-off of the heat­ ing current to 46 °C, at which temperature the cartridges were re­ moved from the furnace.

The ampule that received the full 1150 °C temperature for the hour-long soak contained tungsten spheres and aluminum. In 1-g, the unmelted tungsten spheres would sink to the bottom. In micro-gravity, they remained in place, and the Soviet scientists measured the rate of formation of tungsten-aluminum alloys during the 1- hour soak.

The middle ampule reached a somewhat lower temperature. It contained germanium "doped" with 2 percent of silicon atoms—a semiconductor used in electronic circuits. The melt solidified direc- tionally, from the cool end toward the hot end of the cartridge. The Soviets considered these germanium silicon crystals to be better than those made in 1-g. 242

The multipurpose electric furnace and its experiments undoubt­ edly had some influence on the design and research programs of the Splav (Alloy) and Kristall furnaces which were later flown on Salyut 6.

salyut stations

Experiments in space technology and studies of the behavior of materials are now a permanent component part of the flight pro­ gram of Salyut orbital stations.

The electric furnace Splav-01 had a mass of 23 kg. The problem of heat insulation was solved by designing the furnace to fit into the waste-disposal air lock.

Splav had three heating areas—one that could maintain tem­ peratures of up to 1100 °C, a "cold" area that could maintain 600- 700 °C, and a "gradient" area along which there was a linear tem­ perature gradient between the maximum and minimum furnace heating capabilities. The furnace was controlled by a computer which ensured an accuracy of plus or minus 5 K of the required temperature. The material samples were in capsules, and each cap­ sule contained three crystal ampules that fused when subjected to heating. This was intended to permit formation of mono-crystals in the "gradient" area, while three-dimensional crystallization would occur in the hot and cold sections of the furnace. 243

The first experiment, which lasted some 14 hours, was made to study diffusion processes in molten metals in microgravity. A cap­sule containing ampules of copper and indium, aluminum and mag­ nesium, and indium antimonide was placed in the furnace. After the airlock was depressurized, the furnace was switched on and the computer monitored the process of crystallization.

During the experiment, the complex was put into the "drift regime, with all its orientation engines switched off, to reduce dy­namic disturbances on the experiment. 244

Splav was later used to investigate the possibilities of obtaining immiscibility-gap alloys—alloys of materials having substantially different densities, such as an alloy based on aluminum and tung­sten. Such experiments are not possible on Earth since a uniform alloy does not form due to the different densities of aluminum (2,700 kg/cubic meter) and tungsten (19,300 kg/cubic meter). In mi­ crogravity, however, they form an alloy which is stronger than steel. Another experiment, said to be of practical interest, was that of impregnating porous molybdenum with gallium to form a super­ conductor. 245

On board Progress 2, which docked with Salyut 6 on July 9, 1978, was a new electric furnace, an improved version of the Splav fur­nace already on board. The new furnace, known as Kristall (Crys­ tal), had a mass of 28 kg and the process of crystallization took place in a different manner.

The substance from which the crystal was to be formed was first placed in a zone where the temperature was reduced; a seeding technique was used which kept one side cold and the other hot. The cold side acted as a seed. The temperature curve was kept con­ stant in space. The sample in the capsule then stretched slowly across the zone, with the same result as in Splav, but temperature control was better, giving crystals that were more regular and ho­ mogeneous.

Kristall was said to be highly automated. It incorporated many kinds of electronic devices enabling the cosmonauts to select vari­ous work programs without interfering in the processes. Whereas Splav was in the airlock chamber, so that heat could be discharged into open space, Kristall had better heat protection and was placed inside the station's transfer section. There was a certain amount of heat from it but the temperature control system was able to cope. 246

The first experiment with Kristall was used to produce a pure monocrystal of gallium arsenide from a high temperature solution by a zone-melting technique. 247

The scientific director of the Kristall experiment, V.T. Khryapov, said the distinguishing feature of the Kristall apparatus was that, in the first place, it could operate inside the orbital station, with out having direct connection to the space vacuum. Second, the fact that the apparatus enabled technological processes to be conducted by four methods in distinction from apparatuses which were used previously.

The first method was that of obtaining monocrystals from the gaseous phase by sublimation; the second was obtaining films of monocrystals by the chemical gas-transportation method; the third method was obtaining monocrystals by what is called the moving solvent method to obtain a high-temperature solution; and the fourth was the traditional method of volumetric-directed crystalli­ zation—the method used earlier. He went on,

It is necessary to conduct pure experiments when the in­ terference which occurs on Earth in the form of convec­ tion, heat distribution is absent; and therefore this re­ search produces materials which, having been obtained in this installation, can be used in instruments. The quantity used in the instruments is very small, measured in milli­ grammes. But in this installation we can obtain grammes of it. 248

Temperature distribution along the axis of the Kristall furnace was measured by experiments with the code name "Imitator." The Imitator-1 experiment employed shaped meltable wires with differ­ ent melting points for control panel settings of 1,100, 900, 800, 600, and 400 °C. In the Imitator-2 experiment, temperature profiles in both steady-state and dynamic modes were measured with 10 nickel-chromium nickel microthermocouples attached to a simulat­ ed ampule. The thermoelectric e.m.f.'s were measured with a digi­tal electronic voltmeter. Good correlation was obtained between re­ sults from both experiments. 249

Kovalyonok and Ivanchenkov performed an experiment to produce optical glass using the furnace delivered by Progress 2. The absence of gravity was expected to improve the microstructure of the glass and provide a surface that required no further treat­ ment. Whereas difficulties were caused in manufacture on Earth by the molten glass touching the walls of the furnace, in space it was possible to carry out the melt and solidification in a state of suspension. 250

Experiments with the furnaces have been a main feature of manned spaceflight operations under the Interkosmos program. During the Soyuz 31 visit to Salyut 6, in August 1978, the Berolina experiment was performed as part of the joint flight program with the G.D.R. At the time, it was said to be likely to have a big influ­ ence on semiconductor technology and component manufacture and thus on the development of electronics in the G.D.R. Lead tel- luride, which serves as a base material in opto-electronics and laser technology, was obtained under conditions of microgravity. 251

Two experiments were performed using both the Splav and Kris- tall furnaces. The Berolina S-l experiment boiled beryllium-thori m glass. A more uniform and higher quality glass could be ob­ tained in space conditions and it was hoped to use this in optical devices such as telescopes, microscopes, cameras, and so on. The second Splav experiment, Berolina S-2, differed from previous ex­ periments in that semiconductor crystals of bismuth-antimony were produced using a special programmed temperature reduction process.

The Kristall experiments used a different crystallization method, employing a computer-controlled mechanical retraction device which slowly withdrew the ampule from the high-temperature zone of the furnace during the cooling process. In the Berolina K-l ex­ periment, lead telluride crystals were grown by sublimation. The Berolina K-2 experiment grew bismuth-antimony crystals of the same composition as in the S-2 experiment so that the results of both processes of crystallization could be compared afterwards and the best crystal-growing method ascertained. 252

Photographs of the Kristall furnace and the ampules used in the Berolina experiments carried out by V. Bykovskiy and S. Jahn on board Salyut 6 were published in Spaceflight. 253 A picture of the Splav-01 appeared in the previous issue. 254

In the March to May 1979 period, a cycle of 10 experiments in space material science, under the general name "El'ma," was car­ ried out by cosmonauts Lyakhov and Ryumin using Splav and the new Kristall furnace, which had been ferried up in Progress 5.

The El'ma experiments, in cooperation with French scientists, who had supplied the sample materials, were devoted to the study of crystallization of aluminum (with copper added) and tin (with lead added) under conditions of microgravitation. The experiments were also devoted to obtaining new magnetic materials; in this work neodymium-cobalt was used, which can be obtained in princi­ ple under Earth conditions, but its structure would be very hetero­ geneous; manganese-caesium, which cannot be obtained under Earth conditions, was also used.

A subsequent group of El'ma experiments was devoted to study­ ing crystallization from a gaseous state (vanadium oxides and ger­ manium were used). Also studied was the influence of spaceflight factors on the crystallization of semiconductor materials from the liquid state in samples of bismuth, tellurium and bismuth-telluri­ um and indium-antimony alloys. Finally, crystallization from gal­ lium-arsenic and gallium-indium-antimony solutions was investi­ gated in two El'ma experiments. 255

The "Khalong" series of experiments devised by specialists of the U.S.S.R., the Socialist Republic of Vietnam, and the German Demo­ cratic Republic, used the Kristall and Splav-01 furnaces to grow crystals of semiconducting compounds. The first three investigated direct crystallization from solid solutions of Bi 2Te2.7SEo.3. BiSbTes, and Bio.sSbi.5Te3. The fourth and fifth experiments, also conducted in the Kristall furnace, concerned the growing of gallium phos­phide crystals from a melt bath by the moving solvent method. In the latter experiment the gallium phosphide was alloyed with zinc and oxygen. The sixth experiment, using the Splav-01 furnace, grew lead telluride and Bi 2Te2.7Seo.3 crystals, with an excess of tel­lurium, in separate ampules in a single capsule. 256 The selection of these materials was based on their having been studied extensively on Earth and possessing electrophysical properties which are ex­ tremely structurally sensitive and growth-condition dependent, their extensive employment in electronics technology, and their suitability for growth in conditions available in the furnaces.

During the Salyut 4 mission it became necessary to resurface the 25 cm-diameter main mirror of the solar telescope. The cosmonauts sprayed a new reflective layer onto it. The process worked well and this was a deciding factor in Soviet plans for future space stations since there would be no point in sending up other telescopes for long duration missions if mirror surfaces could not be recoated.

On Salyut 6, experiments involving the vacuum deposition of coatings were performed using the "Isparitel" (vaporizer) unit. Electrons emitted by an electron gun situated in a vacuum bom­ bard the molten metal located in a refractory crucible. The metal is vaporized and deposited on a plate. The window through which the metal vapors fall on the plate is opened and closed by a blind. The thickness of the deposited metal layer, which is proportional to the time for which the window is open, can be regulated. Developed by the same Institute as the Vulkan unit, Isparitel consisted of the working unit with two electron guns and a manipulator for chang­ ing the deposited plates installed in one of the air locks. These were electrically connected to the remote control panel. Two cos­ monauts were needed to perform the experiment. One monitored the instrument readings and operated the controls while the other kept a precise time count of the vapor deposition using a stop­watch. Plates were coated on both sides and each one had its own exposure time.

Analysis back on Earth of the coatings of several samples showed that the film did not lose its mirror quality at thicknesses greater than the designed value. Thus it would appear that, in micrograv ity, it is possible to obtain a stronger mirror coating than under ground conditions. 257

Following the final series of coating experiments, the cosmonauts removed the Isparitel unit from the airlock and installed the Splav electrical furnace in its place.

future outlook

At the end of 1979, the Director of the Space Research Institute [IKI], Sagdeyev, interviewed during a seminar sponsored by the Znaniye (knowledge) Society in Tallin on "The Latest Achieve­ ments in Space Research and Problems of Propaganda" said, "I am certain that in the next 5-10 years a vast amount of industrial ac­ tivity will begin in orbit. Toward that end we must prepare not only technology but men as well." 258

Writing on the occasion of the 25th anniversary of the first satel­ lite launching, Academician Glushko commented that satellite methods enable monitoring of the degree of pollution of the Earth and the effectiveness of means used to protect its biosphere. He went on to add that among radical measures for protecting the Earth from contamination, depletion and overheating is putting major industry and energy facilities beyond its confines in outer space. He wrote,

In the first instance, industrial production should be or­ganized in space making use of the unique properties such as weightlessness, clean vacuum, low temperature and solar energy, and production of unique materials that would be impossible or unprofitable to organize under ter­ restrial conditions. This pertains primarily to the manu­ facture of crystalline, optical and semiconductor materials, and some medicines.

Processes are being worked out under space conditions for soldering, welding, melting, assembly installation, ap­ plying coatings; automatic machines are being designed that are capable of constructing standard components of large-scale structures. These are but the first steps on the road to the inevitable industrialization of space. 259

These two quotations are indicative of Soviet thought as to the manner in which space processing should develop. Already there is evidence from the Salyut 7 missions that some of these measures are in hand. Electrophoretic techniques have been employed for the separation of tissue cells in the Tavriya experiment.

In the distant future one might expect the Soviets to take steps to establish a permanent space station in geosynchronous orbit for the purposes of industrial production under conditions of microgravity and also for the collection of solar energy, its conver­ sion to electrical energy and transmission to Earth by microwaves, but these introduce difficulties several orders of magnitude greater than those solved to date.

At the beginning of this chapter, it was reported that the Rus­ sians were initially slow to exploit space although their writers had been quick to recognize the potential applications for a wide varie­ ty of purposes. However, from what has been recorded above, it can be seen that the Soviet space program has made great strides during the period under review and now appears to be totally com­ mitted to maintaining a steady and purposeful advance toward the exploitation of its results for the benefit of the Soviet system

GEODESY AND MAPPING

Table 39 classifies spacecraft whose orbits have periods greater than those of similar navigation satellites as possible geodetic missions. That table also includes the F-2 launched Kosmos 1045 at 82.5° with an orbital period of 120 minutes because its orbital elements were closer to those of the geodetic class of payload than any other and, for that reason, perhaps Kosmos 1312 and Kosmos 1410, launched in 1981 and 1982 respectively, together with Kosmos 1510 launched in 1983 with the unusual 73.6° inclination, all with periods close to 116 min, should also be considered as possible candidates for such a mission.

All flights of recoverable satellites in the special subset presumed to carry out mapping missions were launched by the F-2 vehicle into orbits with 82.3° inclination and transmitted simple f.s.k. beacons on 19.994 MHz. These were Kosmos 1239 and Kosmos 1309 in 1981 and Kosmos 1332 and 1398 in 1982. TL recovery beacons were received by the Kettering Group from the last three of these missions. For consistency, details of these satellites are given in table 6 d. There were no flights in this category during 1983.

Notes:

1. Kosmos launches subdivided by launch site and inclination. The Kosmos number is followed by the flight duration in days in parentheses

2. The letter F indicates that a TF recovery beacon was observed by the Kettering Group.

3. Flights announced as. performing Earth resources missions are indicated by the letters EB, or P if announced as reporting to the Priroda (Nature) Center.

4. A subset of the F-2 launched flights also maneuvers to a higher, near circular orbit toward the end of the first day and are shown in the final column for convenience.

Notes:

1. Kosmos launches subdivided by launch site and inclination. The Kosmos number is followed hy the flight duration in days in parentheses.

2. Although on UHF transmissions were intercepted from Kosmos 1516, its orbital parameters and flight duration suggest that it belongs in this category.

Notes:

1. The Kosmos number is followed by the flight duration in days in parentheses.

2. The medium resolution (?) flights have also been included in table 6(b).

3. The mapping and geodesy flights of 1981 and 1982 transmitted on 19.994 MHz.

4. The letters F, K, and L indicate that a TF, TK, or TL recovery beacon was observed by the Kettenng Group.

5. Flights announced as performing Earth resources missions are indicated by the letters ER, or P if announced as reporting to the Priroda (Nature) Center.

References:

A. SOVIET SPACE PROGRAMS: 1976-80 (WITH SUPPLEMENTARY DATA THROUGH 1983), UNMANNED SPACE ACTIVITIES, PREPARED AT THE REQUEST OF Hon. JOHN C. DANFORTH, Chairman, COMMITTEE ON COMMERCE, SCIENCE, AND TRANSPORTATION, UNITED STATES SENATE, Part 3, MAY 1985, Printed for the use of the Committee on Commerce, Science, and Transportation, 99th Congress, 1 st. session, COMMITTEE PRINT, S. Prt. 98-235, U.S. GOVERNMENT PRINTING OFFICE WASHINGTON : 1985

133 Strange, W.E., and L.D. Hothem. Phil Trans R. Soc. Lond. A, vol. 294, 1980, pp. 335-340.

134 Kutuzov, I.A., and Yu. P. Kiyenko. Issledovaniye Zemli iz Kosmosa, No. 1, 1980, pp. 79-87.

229 Aviation Week & Space Technology, vol. 106, No. 8, Feb. 21, 1977, p. 19.

230 Soviet Space Programs: 1976-80. Washington, U.S. Government Printing Office, December 1982, pp. 235-240.

231 National Paper: U.S.S.R., Sept. 2, 1981, pp. 55-62.

232 Idem.

235 Perry, G.E., in "Outer Space—A New Dimension of the Arms Race," ed. Jasani, B., S.I.P.R.I. London, Taylor and Francis, 1982, p. 141.

236 Aviation Week & Space Technology, vol. 113, No. 12, Sept. 22, 1980, pp. 14-15.

237 Yevich, A.F. Industriya v kosmose, Moskovskiy rabochiy, 1978.

238 The traditional terms "weightlessness" or "zero-g" are not strictly accurate. A body expe riencing an acceleration is acted upon by an external force. In an orbiting spacecraft, such forces arise as results of drag, thruster action, and crew movement. Even a rotation demands a centripetal acceleration for all points of the body distant from the center of rotation. Conse­ quently, the term "microgravity is currently used to encompass the variety of small accelera tions experienced in orbit.

239 Kubasov, V. Pravda, Apr. 26, 1980, p. 3.

240. Idem.

241 . Ezell, E.C., and Linda N. Ezell. "The Partnership," NASA SP-4209, Washington, DC, 1978, app. E, pp. 533-535.

242 "ZeroG Technology," NASA EP-140, Washington, DC, Oct. 1977, pp. 21-22.

243 Grishin, S.D., Moscow Home Service, Feb. 21, 1978, 0800 G.m.t.

244 Tass, Moscow, Feb. 15, 1978, 1234 G.m.t.

245 Grishin, S.D., op. cit.

246 Grishin, S.D. Moscow Home Service, July 9, 1978, 1700 G.m.t.

247 Tass, Moscow, July 17, 1978, 1242 G.m.t.

248 Khryapov, V.T. Moscow Home Service, Aug. 1, 1978, 0800 G.m.t.

249 Gorbatko, V.V., et al. Kosmicheskiye Issledovaniya, vol. 20, No. 2, March-April 1982, pp. 310-312.

250 Tass, Moscow, July 14, 1978. 1700 G.m.t.

251 Herrmann, R. ADN, Aug. 28, 1978. 1743 G.m.t.

252 Grishin, S.D. Moscow Home Service, Aug. 30, 1978. 1530 G.m.t. 253 Spaceflight, London, vol. 21, 1979, p. 131.

254 Spaceflight, London, vol. 21, 1979, p. 56.

255 Kotel'nikov, V., Izvestiya, June 28, 1982, p. 2.

256 Idem.

257 Kalinin, A. Aviatsiya i Kosmonavtika, No. 12, Dec. 1980, pp. 44-45.

258 Sagdeyev, R. Sovetskaya Estoniya, Tallin, Dec. 7, 1979, p. 1.

259 Glushko, V.P. Zemlya i Vselennaya, No. 5, September-October 1982, pp. 4-10.