Kosmos 122 (Russian: Космос 122 meaning Cosmos 122), launched on 25 June 1966, Meteor No.5L, and was one of eleven weather satellites put into orbit between 1964 and 1969. This launch was dubbed a Kosmos satellite mission because that was the designation given to prototype satellites by the Soviet Union. Kosmos 122 was the first announced Russian meteorological satellite and the last in a series of prototype meteorological satellites that included Kosmos 44 (28 August 1964), Kosmos 58 (26 February 1965), Kosmos 100 (17 December 1965), and Kosmos 118 (11 May 1966). It was the last meteorological satellite launched from the Baikonur site with a Vostok-2M launch vehicle at an orbital inclination of 65.0°, and it provided a transition from the prototype series to the Kosmos "Meteor" experimental weather satellite system. The deployment of two other satellites, Kosmos 144 (28 February 1967) and Kosmos 156 (27 April 1967), helped create the first Soviet weather forecasting network. Kosmos 122 and the other satellites had two cameras on board, one high resolution and one infrared in order to see the weather day or night. The Kosmos 122 was a successful mission and this specific satellite was used for four months. These satellites were used until 1969 when they were replaced with an upgraded model officially called Meteor.
Spacecraft The satellite was in the form of a large cylindrical capsule, 5 metres (16 ft) long and 1.5 metres (4 ft 11 in) in diameter. Two large solar cell panels of three segments each were deployed from opposite sides of the cylinder after satellite separation from the launch vehicle. The solar panels were rotated to constantly face the Sun during satellite daytime by means of a Sun sensor-controlled drive mechanism fitted in the top end of the center body. The meteorological instruments were housed in a hermetically sealed compartment located in the lower part of the capsule, while the basic satellite servicing systems were contained in a special hermetically sealed compartment in the upper part of the capsule. Data were transmitted to Earth at a frequency of 90 MHz by means of a steerable high-gain parabolic antenna that was attached to the center section of the satellite body by a long arm. The satellite was triaxially stabilized by a series of inertial flywheels, driven by electric motors, whose kinetic energy was dampened by torques produced by electromagnets interacting with the Earth's magnetic field. Kosmos 122 was oriented by Earth sensors with one of its axes directed Earthward along the local vertical, a second oriented along the orbital velocity vector, and a third oriented perpendicular to the orbital plane. This orientation ensured that the optical axes of the instruments were constantly directed Earthward.
Instruments The instrumentation consisted of two vidicon cameras for daytime cloud cover pictures, a high-resolution scanning infrared (IR) radiometer for nighttime and daytime imaging of the Earth and clouds, and an array of narrow-angle and wide-angle radiometers for measuring the intensity of radiation reflected from the clouds and oceans, the surface temperatures of the Earth and cloud tops, and the total flux of thermal energy from the Earth-atmosphere system into space, respectively. The experiment terminated operations in October 1966.
Dual vidicon cameras The Kosmos 122 dual vidicon camera experiment was designed to test the capability of Russian weather satellites to provide daytime pictures of the Earth's cloud cover distribution, local storms, and global weather systems for use by the Soviet Hydrometeorological Service. The instrumentation consisted of two identical vidicon cameras that were mounted in the satellite base and were directed toward the Earth. Each camera viewed a 500 kilometres (310 mi) by 500 kilometres (310 mi) area – one to the left and the other to the right of nadir – with a resolution of 1.25 kilometres (0.78 mi) at nadir from a satellite altitude of 600 kilometres (370 mi) to 700 kilometres (430 mi). The cameras took a one-frame image of the Earth's cloud cover with slight overlapping of successive frames to provide continuous coverage. The cameras switched on automatically any time the sun was more than 5° above the horizon. Because the Earth illumination varied so much, automatic sensors adjusted the camera apertures to produce high-quality pictures under a variety of illumination conditions. The image formed by each vidicon tube either was transmitted directly to the ground if the satellite was in radio contact with one of two ground stations or was recorded on magnetic tape for later transmission if the satellite was beyond the zone of radio communication. The TV images received by these ground stations were processed and transmitted to the Hydrometeorological Center in Moscow, where they were analyzed and used in various forecast and analysis products. The pictures were archived at the Hydrometeorological Center. The Kosmos 122 cameras, although having 2.5 times the resolution of those carried on the ESSA satellites, could not provide continuous overlapping global coverage as do the ESSA cameras owing to the lower orbit of the Kosmos 122 satellite (650 kilometres (400 mi) compared to 1,400 kilometres (870 mi)). Thus, to close the gaps in coverage, at least two satellites were required in the weather satellite system. In addition, cloud cover mosaics were produced from 10 or more individual cloud cover pictures at the Hydrometeorological Center to provide a more comprehensive view of global weather systems. Some of the individual pictures and the cloud mosaics were transmitted to various foreign meteorological centers as part of an international meteorological data exchange program. The United States received some of these pictures at the National Environmental Satellite Service (NESS) in Suitland, Maryland, via the "cold line" facsimile link with Moscow. Pictures were transmitted to NESS from September 11, 1966, through October 26, 1966. These pictures were archived at NESS for 1 yr and then, unless of unusual interest, were discarded.
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