MIR: Expedition 15
(EO-15)

Launch from the Baikonur Cosmodrome; landing 112 km northeast of Arkalyk.

Following a two day solo flight Soyuz TM-18 docked with the MIR space station on January 10, 1994. The three cosmonauts became the 15th resident crew of the MIR. Research work by Valeri Polyakov during his long-term flight was done. He accomplished 25 different experiments in space flight medicine.

The experiments concerned mainly the diet, the function of the muscular system, the lungs and the immune system. Changes of the blood and the nervous system were analysed, too. Furthermore, problems with the metabolism (red blood cell, erythrocite), alterations of the blood volume and the function of the sense of balance in the middle ear were examined. One used the experiment called VOG (Video OkluGraphie), which the german mission brought on board of the space station in 1992. The Russian flight control centre transmitted the data to Oberpfaffenhofen, Germany, from where the specialists could influence the experiment. Another subject of investigation was the depletion of calcium in the bones during a long-term stay in zero gravitiy.
It is unknown whether the depletion of calcium stops at certain level. Scientifics believe that a depletion of 20% is highly dangerous. In order to counteract the negative alterations of the tissue of muscles and bones the advanced vacuum trousers KARKAS were used. Those trousers suck the blood in the abdomen. Thus, the situation of a higher blood volume in the abdomen due to gravity on earth is simulated. The measurement of the enlargement of the circumference of the leg, the blood pressure, the cardiac output, the change of position of the heart in the thorax and the noises of the blood stream were taken. The two guinea pigs Viktor Afanasiyev and Yuri Usachyov underwent this procedure every third day.

The sleep of the cosmonauts and the coordination of cognition and movement were also examined. The spacemen got fixed on the floor but could still move their heads and arms. A monitor screen transmitted different visual appeals and four infrared cameras recorded the reactions. The results of the tests are believed to be important for movement disorders on earth. In the psychological experiment PSY the mental and psychomtor ability of Valeri Polyakov were tested over several months. Reaction rate, short-term memory, attention and manual skills were tested.

There were also nonmedical researches on the field of material sciences. There was a research concerning the behaviour of undercooled melting (experiment TES). Eleven samples, which were enclosed in a shell of glass, were first melted and then refrigerated. Because of the lack of crystal nuclei the liquid state can be kept below the usual temperature of solidification. Depending on the temperature the samples solidify with different microstructures. The data of the experiments were evaluated via the system DATAMIR and transmitted to earth. The system DATAMIR was developed in Austria and is on board of the station since 1991. DATAMIR controls the experiment, records the data, visualises the results und forwards them to the system of telemetry at the space station. The possibility of mould formation at non-metallic materials was investigated.

Earth exploration, astrophysics and biotechnology were very important, too. The multichannel spectrometer MKS-MS and FASA came into operation. Hundreds of pictures of the earth were taken with the multichannel camera MKF-6MA. The intensity of the radiation of energy and particles was measured in and about the space station. As far as astronomic objects were concerned, their x-radiation and their gamma radiation were especially interesting. In the experiment RESONANZ the stability of the station complex was estimated.

A new, camera-based navigation system was tested on the unmanned transport space ship Progress M-21. The new system works even if the navigation system Kurs does not work. The flight engineer receives a complete picture of the approach via three cameras and is able to dock the space ship by a manual control. Supply goods and research materials arrived at the space station during the six months lasting mission by the transport space ships Progress M-22 and M-23.