Acquisition of meteorological information needed for use by the weather service. References: 1 , 2 , 5 , 6 .

Ocean surveillance; nuclear powered. References: 1 , 2 , 5 , 6 .

Carried Oleg Makarov, Vasili Lazarev for rendezvous with Salyut 4; but during second-third stage seperation third stage failed to separate from second stage but still ignited. The crew demanded that the abort procedures be implemented but ground control could not see the launch vehicle gyrations in their telemetry. Soyuz finally was separated from by ground control command at 192 km, and following a 20.6+ G reentry, the capsule landed in the Altai mountains, tumbled down a mountainside, and snagged in some bushes just short of a precipice. The crew was worried that they may have landed in China and would face internment, but after an hour sitting in the cold next to the capsule, they were discovered by locals speaking Russian. Total flight duration was 1574 km and flight time 21 minutes 27 seconds. Lazarev suffered internal injuries from the high-G reentry and tumble down the mountain side and never flew again. Both cosmonauts were denied their 3000 ruble spaceflight bonus pay and had to apeal all the way to Brezhnev before being paid. References: 42 , 32 , 33 , 60 .

Ocean surveillance; nuclear powered. References: 1 , 2 , 5 , 6 .

Investigation of the upper atmosphere and outer space. References: 1 , 2 , 5 , 6 , 99 .

Geodynamics Experimental Ocean Satellite. The mission of GEOS 3 (Geodynamics Experimental Ocean Satellite) was to provide the stepping stone between the National Geodetic Satellite Program (NGSP) and the Earth and Ocean Physics Application Program. It provided data to refine the geodetic and geophysical results of the NGSP and served as a test for new systems. A major achievment was the flight of a radar altimeter. Further mission objectives: intercomparison of tracking systems, investigation of solid-earth dynamic phenomena through precision laser tracking, refinement of orbit determination techniques, determination of interdatum ties and gravity models, and support of the calibration and position determination of NASA Spaceflight Tracking and Data Network (STDN) S-band tracking stations. References: 1 , 2 , 5 , 6 .

Military navigation satellite. References: 1 , 2 , 5 , 6 .

Operation of the long-range telephone and telegraph radiocommunications system in the USSR; transmission of television programmes to stations in the Orbita network. References: 1 , 2 , 5 , 6 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Area survey photo reconnaissance satellite; returned film capsule; separated science capsule. References: 1 , 2 , 6 .

KH-8 type satellite. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A). References: 1 , 2 , 5 , 6 .

Maximum Speed - 1279 kph. Maximum Altitude - 17650 m. Flight Time - 450 sec. References: 49 , 97 .

Atmospheric research. Experimental satellite for satellite technology and some scientific experiments. Launched from a cosmodrome in the USSR. References: 1 , 2 , 5 , 6 .

Military navigation satellite. References: 1 , 2 , 5 , 6 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Uncertain if Molniya-1T model was Molniya-1 or Molniya-1T. Operation of the long-range telephone and telegraph radiocommunications system in the USSR; transmission of television programmes to stations in the Orbita network. References: 1 , 2 , 5 , 6 .

In response to the Ministry of Defence's guidelines for third generation launch vehicles, the Ministry of General Machine Building issued instructions for Chelomei to study boosters meeting the military's requirements. These included Lox/Kerosene propellants in place of the toxic N2O4/UDMH favoured previously. Chelomei's competitor in the design, Glushko, was then head of NPO Energia which included Glushko's former OKB-456 engine design bureau. Therefore Chelomei was forced to propose using Kuznetsov Lox/Kerosene engines from the cancelled N1 moon program.The use of existing Proton tankage tooling for the stages and the Kuznetsov engines would allow a high-performance vehicle to be developed at minimum cost. However Chelomei was out of favour, Kuznetsov was discredited after the N1 fiasco, and Glushko was ascendant. The proposal stood no chance. Glushko's Zenit launch vehicle became the accepted solution.

Under US pressure Italy had signed the Nuclear Non-proliferation Treaty on 2 May 1975. Work on nuclear-tipped ballistic missiles ended.

Maximum Speed - 1541 kph. Maximum Altitude - 22370 m. Flight Time - 448 sec. References: 49 , 97 .

Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C). References: 1 , 2 , 5 , 6 .

Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B). References: 1 , 2 , 5 , 6 .

American merchant ship Mayaguez, seized by Cambodian forces, is rescued in operation by U.S. Navy and Marines, 38 of whom are killed

D5A: Weight 36 kg. Testing in space of a hydrazine catalytic decomposition micropropulsion unit. Responsible organization: Societe Europeene de Propulsion. D5B: Weight 76 kg. Testing in space of the CACTUS accelerometer (ultrasensitive triaxial capacitive accelerometric sensor). Responsible organization: ONERA, Chatillon-sous-Berneux, France. References: 1 , 2 , 5 , 6 .

D5A: Weight 36 kg. Testing in space of a hydrazine catalytic decomposition micropropulsion unit. Responsible organization: Societe Europeene de Propulsion. D5B: Weight 76 kg. Testing in space of the CACTUS accelerometer (ultrasensitive triaxial capacitive accelerometric sensor). Responsible organization: ONERA, Chatillon-sous-Berneux, France. References: 1 , 2 , 5 , 6 .

Unusable orbit. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A). References: 1 , 2 , 5 , 6 .

Unusable orbit. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A). References: 1 , 2 , 5 , 6 .

Area survey photo reconnaissance satellite; returned film capsule; separated science capsule. References: 1 , 2 , 6 .

Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C). Launch vehicle put payload into geosynchronous transfer orbit References: 1 , 2 , 5 , 6 , 278 .

Max. altitude. Maximum Speed - 1744 kph. Maximum Altitude - 22370 m. Flight Time - 461 sec. References: 49 , 97 .

Wings on dock, Palmdale-less elevons, seals and main gear doors-Enterprise (OV-101) References: 15 .

First use of the Minuteman I booster, replacing the Atlas, for the ABRES program. References: 88 .

Defense Meteorological Satellite Program. References: 1 , 2 , 5 , 6 .

Manned two crew. Docked with Salyut 4. Joint experiments with the Salyut scientific orbital station. Recovered July 26, 1975 14:18 GMT. Landed 56 km E Arkalyk. References: 1 , 2 , 6 , 32 , 33 , 60 .

Vertical stabilizer on dock, Palmdale (main fin box only), Enterprise (OV-101) References: 15 .

Eight satellites launched by a single carrier rocket. References: 1 , 2 , 5 , 6 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Zenit-2M (area survey photo reconnaissance) satellite used for earth resources studies as part of 'Gektor-Priroda' project. Investigation of the natural resources of the earth in the interests of various branches of the national economy of the USSR and international cooperation. References: 1 , 2 , 6 , 103 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Uncertain if Molniya-1T model was Molniya-1 or Molniya-1T. Operation of the long-range telephone and telegraph radiocommunications system in the USSR; transmission of television programmes to stations in the Orbita network. References: 1 , 2 , 5 , 6 .

Central Committee of the Communist Party and Council of Soviet Ministers Decree 178 'On development of the 11A511U2 launch vehicle' was issued. References: 474 .

SRET 2 technological research and study satellite. Launched from Soviet Union with a Soviet launch vehicle with the Molniya satellite. Mass 30 kg. Study of the behaviour of a passive cryogenic radiation system, study of the aging of thermal casings and pl astic films. References: 1 , 2 , 5 , 6 .

Maximum Speed - 1786 kph. Maximum Altitude - 21980 m. Flight Time - 474 sec. References: 49 , 97 .

KH-9 type satellite. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A). References: 1 , 2 , 5 , 6 .

Combined Venus orbiter/lander mission. After separation of the lander, the orbiter spacecraft entered Venus orbit and acted as a communications relay for the lander and explored cloud layers and atmospheric parameters. On October 20, 1975, the Descent Craft was separated from the Orbiter, and landing was made with the sun near zenith at 05:13 GMT on October 22. The Descent Craft included a system of circulating fluid to distribute the heat load. This system, plus precooling prior to entry, permitted operation of the spacecraft for 53 min after landing. The landing was about 2,200 km from the Venera 10 landing site. Preliminary results indicated: (A) clouds 30-40 km thick with bases at 30-35 km altitude, (B) atmospheric constituents including HCl, HF, Br, and I, (C) surface pressure about 90 (earth) atmospheres, (D) surface temperature 485 deg C, (E) light levels comparable to those at earth midlatitudes on a cloudy summer day, and (F) successful TV photography showing shadows, no apparent dust in the air, and a variety of 30-40 cm rocks which were not eroded. Venera 9 and 10 were the first probes to send back black and white pictures from the Venusian surface. They were supposed to make 360 degree panoramic shots, but on both landers one of two camera covers failed to come off, restricting their field of view to 180 degrees. Parameters are for Venus orbit. References: 1 , 2 , 5 , 6 , 67 , 274 , 296 , 428 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Environmental research. The experiments selected for Nimbus-6 were the earth radiation budget (ERB), electrically scanning microwave radiometer (ESMR), high-resolution infrared radiation sounder (HIRS), limb radiance inversion radiometer (LRIR), pressure modulated radiometer (PMR), scanning microwave spectrometer (SCAMS), temperature-humidity infrared radiometer (THIR), tracking and data relay experiment (T+DRE), and the tropical wind energy conversion and reference level experiment (TWERLE). This complement of advanced sensors was capable of mapping tropospheric temperature, water vapor abundance, and cloud water content; providing vertical profiles of temperature, ozone, and water vapor; transmitting real-time data to a geostationary spacecraft (ATS 6); and yielding data on the earth's radiation budget. References: 1 , 2 , 5 , 6 .

The orbiter spacecraft entered Venus orbit and was separated from the lander on October 23, 1975. The lander touched down with the sun near zenith, at 05:17 GMT, on October 25. A system of circulating fluid was used to distribute the heat load. This system, plus precooling prior to entry, permitted operation of the spacecraft for 65 min after landing. During descent, heat dissipation and deceleration were accomplished sequentially by protective hemispheric shells, three parachutes, a disk-shaped drag brake, and a compressible, metal, doughnut-shaped, landing cushion. The landing was about 2,200 km distant from Venera 9. Preliminary results provided: (A) profile of altitude (km)/pressure (earth atmospheres) / temperature (deg C) of 42/3.3/158, 15/37/363, and 0/92/465, (B) successful TV photography showing large pancake rocks with lava or other weathered rocks in between, and (C) surface wind speed of 3.5 m/s. Venera 9 and 10 were the first probes to send back black and white pictures from the Venusian surface. They were supposed to make 360 degree panoramic shots, but on both landers one of two camera covers failed to come off, restricting their field of view to 180 degrees. References: 1 , 2 , 5 , 6 , 67 , 274 , 296 , 428 .

Orbiting Solar Observatory. Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B). References: 1 , 2 , 5 , 6 .

Investigation of the upper atmosphere and outer space. References: 1 , 2 , 5 , 6 , 99 .

High resolution photo reconnaissance satellite; returned film capsule; maneuverable. References: 1 , 2 , 6 .

Maximum Speed - 1427 kph. Maximum Altitude - 17680 m. Flight Time - 426 sec. References: 49 , 97 .

Area survey photo reconnaissance satellite; returned film capsule; separated science capsule. References: 1 , 2 , 6 .