Okean

In the late 1970's the USSR began testing a series of new instruments which would complement the standard meteorological payloads while at the same time would provide specific data on ocean and ice conditions. The heavy reliance of the USSR on its merchant marine fleet for both domestic and international commerce, particularly in the northern latitudes which are subject to extreme environmental conditions, prompted the State Committee on Hydrometeorology to develop specialized spacecraft capable of providing direct operational assistance to ships at sea as well as to a host of other government agencies and civilian and military organizations.

After testing various equipment on four spacecraft (Kosmos 1076, Kosmos 1151, Interkosmos 20, and Interkosmos 21) launched during 1979-1981, the first prototype Okean satellite (Okean-OE) was orbited in 1983 as Kosmos 1500 and was followed by Kosmos 1602 (1984), Kosmos 1766 (1986), and Kosmos 1869 (1987). The first operational spacecraft (Okean-O) was launched in 1988 as Okean 1 and was joined in 1990 by Okean 2.

This Okean-O program is designed

• "to estimate the potential reserves of the energy of tides and the accumulated energy of solar radiation;
• to study the World Ocean as a global damper and regulator of heat and moisture content of the atmosphere;
• to detect zones of upwelling and higher bioproductivity;
• to study subsurface circular eddies and their effect on the formation of destructive cyclones and typhoons;
• to ensure the safety of navigation and control of the ice situation in the Arctic and Antarctic;
• to study the dynamics of sea currents, and the processes of self-purification of seawater and cleansing of river effluents; and
• to control the intensity of pollution of the oceans with oil and oil product discharges."

Okean spacecraft with their electro-optical and radar sensors are designed and manufactured by the Ukranian Yuzhnoye Scientific Production Association of Dnepropetrovsk and are described in detail in the section on Ukranian Earth observation systems. Perhaps the last Russian-sponsored Okean spacecraft, Okean 4, was launched on 11 October 1994 by a Tsyklon-3 booster from the Plesetsk Cosmodrome into an orbit of 632 km by 666 km at an inclination of 82.5 degrees. Okean 4's predecessor, Okean 3, had ceased working in January of 1994 (References 668-669).

1981-1987 OCEANOGRAPHIC SATELLITES

Okean-O satellites, introduced with Cosmos 1500 in 1983 have the primary task of observing the ice situation in the Arctic and Antarctic under conditions of cloudy weather and polar night. An important feature of these satellites is the capability of transmit­ ting information to simplified reception stations such as are found at polar stations or onboard ships. These satellites are currently operational. Side-looking radar provides one kilometer resolution with a swath-width of 450 kilometers. 71 The radar was designed by scientists at the Kharkov Institute of Radio Physics and Electronics of the Ukranian Academy of Sciences under the direction of Anato- liy Kalmykov. 72 The head of the department of remote sensing of the Academy's Marine Hydrophysical Institute, Yuri Terekhin, claimed that Cosmos 1500 supplied valuable information to 53 re­ search stations in various parts of the Soviet Union. 73 The radar was said to be almost the same as that carried by Venera 15 and Venera 16 to map the cloud-covered surface of Venus. 74

In addition the satellites carry scanning and non-scanning three-channel SHF radiometers, which are able to detect surface thermal radiation within a radius of 330 km from the sub-satellite point and which have become "indispensable for obtaining images of cold and warm currents, compiling temperature charts, and calculating the speed of winds, rough sea zones and areas of intense precipita­ tion." 75

Papers presented at the 35th Congress of the I.A.F. in Lausanne, Switzerland, described the instrumentation and modes of operation of Cosmos 1500. 76 The side-looking radar operates at a wavelength of 3.15 cm, providing 1.52 km resolution over a viewing field of 460 km. An improved multichannel low-resolution scanner provides im­ agery in the four spectral bands: 0.5-0.6; 0.6-0.7; 0.7-0.8; 0.8-1.1 mi­ crons. The viewing field from the height of 650 km is 1,930 km with a ground resolution of 1.5 km. The side-looking radar and the mul- tispectral scanner can function simultaneously, having the same line scanning uniform at the Earth's surface. The satellite informa­ tion system is capable of either performing direct transmission or preliminary recording by the memory and subsequent reproduction within the radio-range of the receiving centers. The memory can store 6.5 minutes of data providing image-strips 2,750 km in length at the swath-widths quoted above. This permitted the production of maps of the Arctic and Antarctic ice-caps. 77

Data are received and processed by the three main centers and at regional centers, shown on a sketch-map, at Leningrad, Petro- pavlovsk-Kamchatka, Yuzhno-Sakhalinsk, and four locations along the northern seaboard of the Soviet Union, and shipboard receiving stations. The 137.4 MHz transmission can provide any of the four- channels of the multispectral scanner; side-looking radar; or the combined frame of the fourth channel of the multispectral scanner and the side-looking radar. A transmission on the international 466 MHz frequency can provide all four channels of the multispectral scanner or the first three channels and the combined frame of the fourth channel and the side-looking radar. 78

Kettering Group observations of the 137.4 MHz transmissions show a scan rate of 4 lines per second, as with the APT from the Meteor-Priroda series. An edge-code resembling a "piano keyboard" is present whenever the side-looking radar image is transmitted. 79

In October 1984 Cosmos 1500 rendered practical help to naviga­ tors in the eastern sector of the Arctic where, in the area of the Long Strait and the port of Pevek, a caravan of ships was icebound. Radar images transmitted from the satellites enabled specialists quickly to assess the ice situation and send information to the ad­ ministration of the Northern Sea Route and directly to the center of sea operations in Pevek. 80

In 1985 the satellite transmissions helped rescue the research ship Mikhail Somov which was ice-bound in the Antarctic. Radar observations made it possible to locate cracks and passages through which the icebreaker Vladivostok sailed thousands of kilometers to reach the Mikhail Somov. slThe tracing of river floods on the terri­ tory of the Soviet Union was described as a "new task" for Cosmos 1500 at the beginning of 1986. 82 Reconstructed pictures of the River Amur and its valley on August 20, 1985, accurately revealed flooded and dry areas, corresponding respectively to darker and brighter spots on the radar imagery. 83

Cosmos 1602 and Cosmos 1766 had similar imagery on 137.4 MHz and the storage capability was observed with Cosmos 1602, Wakelin receiving a visible image of Japan at Sunningdale on November 29, 1984. The numerical edge-code gave a minute-count between 376 and 380 minutes after midnight Moscow Standard Time, some six and one quarter hours earlier, when Cosmos 1602 was southbound down the east coast of the Peoples Republic of China.

Cosmos 1766 was reported as having taken over regular control of the Arctic seaway in September 1986. Its radar was said to be capable of determining the difference in the thickness of ice, sections of sea free from ice and the movement of ice fields. The data was aiding specialists in outlining optimum routes for vessels moving along the Arctic coast. 84 The side-looking radar onboard Cosmos 1766 was described as the first "industrial" model. 85

Plans to expand the Okean-O system suffered a partial setback in 1987. Cosmos 1869 was launched into a plane 60° away from Cosmos 1766 so that it followed it some two orbits later. However, the side-looking radar antenna failed to deploy correctly. 86 Con­ trary to the belief that no attempt was made to activate the radar for fear of damaging other equipment, Leslie Currington at Welwyn Garden City, England, did receive imagery with the piano-key edge-code, characteristic of transmissions of radar imagery, on August 5, but the imagery was of very poor quality and he did not make a hard copy before erasing the tape. The replacement prom­ised for early 1988 67had still not put in an appearance by June 1. Nevertheless, other equipment onboard Cosmos 1869 functioned normally and stored imagery was received in September 1987. 88

Although Cosmos 1500 was launched in 1983 it is included in table 19, which lists all Okean-O satellites, for completeness.

TABLE 19. —COSMOS SATELLITES IN THE OKEAN-O PROGRAM

Cosmos number and designator Launch Dale Apogee Perigee incl. orbital period

1500 83-99A ......................... 9/28/83 679 649 82.6 97.8

1602 84-105A ........................ 9/28/84 680 648 82.5 97.8

1766 86-55A ......................... 7/28/86 679 648 82.5 97.8

1869 87-62A ......................... 7/16/87 679 647 82.5 97.8

Notes:

• All satellites were launched from Plesetsk by the F-2.
• Apogee and perigee heights in kilometers, inclination in degrees, and orbital period in minutes.
• Orbital data, which may differ from that given in the Master Log, has been computed Irom two line orbital element sets provided by NASA's
  Goddard Space Flight Center.
• Table prepared for Ibe Congressional Research Service by G. E. . Perry.

Numerical Edge-Codes of Okean-O Satellites

A reply from the USSR State Committee for Hydrometeorology and Control of Natural Environment to an inquiry by Dieter Os- lender, of Bonn-Rottgen, West Germany, about the interpretation of the numerical edge code on the APT images received from satel­ lites of the Cosmos 1500 type revealed that the number which ap­pears on line 3, immediately below the gradation wedge, could take one of only 64 possible values. It was shown that, by expressing the value as a 12-bit binary number and selecting the appropriate bits, seven other parameters relating to the status of the onboard in­ strumentation could be identified in lines 4 through 12. 89

S.S. Khodkin's reply confirmed that the number on line 1, above the gradation wedge (line 2), is the time in minutes after midnight (Moscow Standard Time) and gave explanations for the other ten numbers which follow the gradation wedge. The onboard time is zeroed automatically every 24 hours or by command. The maxi­ mum relative error of satellite time is no worse than ± 5 microse­conds in the course of every 24 hours. The error between satellite time and standard time is 0.1 second. The error of the time of re­ setting to standard time is 0.1 second. The indicated satellite time (in minutes) corresponds to the moment of transition from the level of the black marking field, located above the onboard time display, to the level of the white field.

The last two numbers on lines 4-12 only are significant. These denote the integer and decimal fraction of the telemetry value in volts to a tolerance of +0.2 V. Identification of the parameters being monitored and the ranges of permissible values for these lines were listed in the first table of Khodkin's reply but, without a knowledge of the transfer characteristics, little more than observa­ tions of trends is possible. The meanings of some terms, which have been reproduced here as found in the original, are not known.

Line 4 monitors the switching on of the master oscillator. Line 5 has two possible interpretations. One measures the position of the turning platform of the MSU-M. The MSU-M scanner is mounted on a turning platform and can deviate depending on the position of the Sun at angles of ± 25° from the vertical with a step of 5°. Al­ ternatively, line 5 could be an indication of the temperature inside the EA033 back-up instrument. Lines 6 and 8 monitor the oper­ ation of the EU2 and EU1 instruments respectively. Line 7 moni­ tors the operation of either the SPM 3 of the primary EA033 in­ strument or the SPM 4 of the back-up EA033 instrument. Lines 9 and 10 monitor the output powers of the metric (VHF) and deci-me tric (UHF) radio transmitters respectively. Line 11 has three possi­ ble interpretations. It monitors the operation of either the SPM 1 of the EA050 instrument in the 3NP-5NP dm mode or the SPM 2 of the EA141 instrument in the 6NP dm mode. Alternatively, line 11 could be analog telemetry of the primary signal processing unit when it is "on".

The seven possible interpretations of line 12 are listed in se­ quence as given in Khodkin's reply. They are:

Telemetry of the body temperature of the device near the motor (level 3): EA050 in the 3NP-5NP dm mode or EA141 in the 6NP dm mode;

Telemetry of the presence of input frequency and IOX pulses of the EA050 in the 3NP-5NP dm mode (level 2); Telemetry of the rotation of the scanning element of the EA141 in the 6NP dm mode (level 2);

Telemetry of the operation of the voltage converter of the EA050 device in the 3NP-5NP dm mode (level 1);

Telemetry of the operation of the voltage converter of the EA141 device in the 6NP dm mode (level 1).

The seventh possibility is analog telemetry of the back­ up signal processing unit when it is "on".

The marking field of coloring the channels of the MSU-M is lo­cated after the twelve lines of service information. 90

A literal translation of Khodkin's reply for the U.S. Air Force 91 containing at least one typographical error is, in general, in good agreement with the Kettering Group version.

Also in 1983, Cosmos 1500 was launched, the third in a series of satellites for the Okean (Ocean) program. It was based on experi­ ence gained with Cosmos 1076 and 1151 and can be considered to be the first of the operational satellites of the Okean-0 type. A full- scale model of Cosmos 1500 was displayed at the 1985 Paris Air Show.

Cosmos 1500 was immediately effective in providing imagery ena­ bling the freeing of Soviet merchant ships trapped by a sudden freeze of ice in the Chukchi and East Siberian Seas. 50 It was subse­ quently announced that Cosmos 1500 was equipped with side-looking radar which had been installed for the first time on an oceano- graphic satellite.

Transmissions at 4 lines/second, discovered on 137.4 megahertz (MHz) in Italy, were shown to emanate from Cosmos 1500 and to be APT stored imagery of the Caribbean. Radar and visible imagery can be displayed contiguously and stored imagery has been used to compile mosaics of the polar ice-caps.

 References:

A . SOVIET SPACE PROGRAMS: 1981-87, SPACE SCIENCE, SPACE APPLICATIONS, MILITARY SPACE PROGRAMS, ADMINISTRATION, RESOURCE BURDEN, AND MASTER LOG OF SPACEFLIGHTS, Part 2, April 1989, Printed for the use of the Committee on Commerce, Science, and Transportation, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, D.C. 1989, Committee print 1981-87- part-2

71. The booklet by Astachkin et al. cites 460 km for the swath-width.

72.. TASS, 0926 GMT, Aug. 9, 1985.

73. TASS, 0800 GMT, Jan. 23, 1984.

74. TASS, 2048 GMT, Nov. 11, 1984.

75. Astachkin, A., et al. op. cit.

76. Afans'ev, Yu.A., et al. The Experimental Oceanographic Satellite Cosmos 1500. 35th Con­gress of the International Astronautical Federation. Lausanne, Switzerland, Oct. 7-1

77. Burtzev, A. I. et al. Monitoring of the Arctic and Antarctic Ice Cover with Cosmos 1500 Satellite Radar Images. 35th Congress of the International Astronautical Federation. Lausanne, Switzerland, Oct. 7-13, 1984.

78. Ibid.

79. An example of this imagery is to be found in Johnson, N. L. The Soviet Year in Space 1986, figure 26. Teledyne Brown Engineering, Colorado Springs, CO., 1987. p. 35.

80. Astachkin, A., et al. op. cit.

81. TABS, 1558 GMT, Nov. 15, 1985.

82. TASS, 1640 GMT, Jan. 21, 1986.

83. Pichugin, A. P. et al. Doklady Akademii Nauk S.S.S.R. Moscow, Sept. 1985. p. 323-326.

84. Moscow. 1600 GMT, Sept. 28, 1986.

85. Daygorodov, G. Sotsialisticheskaya Industriya, Moscow, Dec. 6, 1986. p. 1.

86. Aviation Week and Space Technology, Oct. 19, 1987, p. 27.

87. Ibid.

88. Kettering Group Technical Memo GP8706, Sept. 9, 1987.

89. Perry, G. E. R.I.G. Newsletter. Leighton Buzzard, England, Sept. 1987. p. 14-15.

90. Perry, G. E. R.I.G. Newsletter. Leighton Buzzard, England, June, 1988. p. 52-55.

A. SOVIET SPACE PROGRAMS: 1981-87, SPACE SCIENCE, SPACE APPLICATIONS, MILITARY SPACE PROGRAMS, ADMINISTRATION, RESOURCE BURDEN, AND MASTER LOG OF SPACEFLIGHTS, Part 2, April 1989, Printed for the use of the Committee on Commerce, Science, and Transportation, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, D.C. 1989, Committee print 1981-87- part-2

49. Lenigradskaya Pravda, Dec. 31, 1987. p. 3.

50. Moscow World Service, 2200 GMT, Nov. 10, 1983