Kwant 2


Crystal is the name of a scientific module, which was docked to the Soviet space station Mir. ( The still popular term Kwant -3 is not officially used. )


Crystal weighed about 20 tons in the initial configuration and was promoted on 31 May 1990 aboard a Proton-K rocket from Baikonur into space. After prolonged autonomous flight to test the systems, the module was successfully docked on 10 June 1990 at the first attempt at the axial port of the docking port of the Mir space station. After docking crystal was rotated by means of a robotic arm on the radial docking compared to the already docked Kvant 2 module. Crystal so that was the third module to extend the space station. The well 60 cubic meters of pressurized compartment of the unit were essentially intended for biology and material science experiments. In addition to the equipment for these experiments, the possessed developed on the basis of TKS ferry module has two enlarged awning with a total of around 70 square meters and own attitude control thrusters.

As a special feature, a coupling node was housed with two androgynous docking points of type APAS 89 (89 for the year of development ) at the rear end instead of the Mercury landing capsule that represented an evolution of the APAS docking device 75 of the Apollo -Soyuz project. This system - unlike ordinary coupling systems - allowed any so-equipped spacecraft to take over both the passive and the active part of a docking maneuver. The new coupling system was developed to allow the docking of the Buran space shuttle to the space station Mir. At the same time special Soyuz spaceships should be equipped with this coupling system to serve as a rescue system for manned test missions of the Buran. In addition, modules were planned to extend the Mir with APAS docking system that should be attached to the crystal.


Although the crystal modules was originally intended for the coupling of Buran space shuttle, was never carried out, such a coupling. After the collapse of the Soviet Union, the Buran program was stopped after an unmanned test flight for financial reasons in 1992. Manned flights of Buran to Mir were therefore never realized. From the Buran program remained a single already -built Soyuz rescue spaceship with the APAS docking system, which was used in January 1993 to transport a crew to Mir ( Soyuz TM -16). This remained the only Soyuz mission in the history of me, when was not docked at the axial docking points of the Mir- Kvant module or the base module.

To permit the continued expansion of Mir, was already implemented in 1992, one of the two large solar panels of crystal by Kwant. Crystal itself was moved due to delays in the production of the next module in May 1995 by 90 ° at a radial docking point of the coupling adapter of me to create enough space for the docking of the Spektr module. Due to the progressive approach of the American and Russian space has been considered to use the crystal module for docking of the American Space Shuttle. Since this threatened due to the size but to touch the modules Kvant -2 and Spektr, or at least their bodies or to damage with firings of the control thrusters, had again done the complicated transformation of the module to the axial port of the Mir- coupling adapter. During the third Shuttle -Mir mission, STS -71 for the first time, the docked space shuttle Atlantis from NASA on 29 June 1995 at Crystal. ( When I was Vormission the only flying around and tested the approach maneuver in the first mission of the program, I was not served. ) The mission followed the deinterleaving of crystal on the original item. As part of the fourth Shuttle -Mir mission was a special shuttle docking module (SDM ) attached to crystal to provide the space shuttle a better docking facility and to avoid the costly conversion at the follow-up missions. Were a total of nine Shuttle missions to Mir, where the docking maneuver ever performed on crystal or the SDM. After some 11 years in space crystal crashed along with the other modules of the Mir complex on 23 March 2001 controls from across the Pacific.

Scientific tasks

With crystal was mainly new technology, mainly tested for heavy docking spacecraft. At first crystal of the advanced power systems that have been tested on the type APAS 89. The additional radial docking was provided for the installation of a large space X-ray telescope, which was to be delivered and docked within the first Buran -Mir mission. After setting the Buran program, however, this could not be achieved, so that the radial docking remained unused until the end of me.

Furthermore, the crystal has been used for research in the fields of biology, geology and astrophysics. In the so-called " Svetlana " experiment a greenhouse to study effects of weightlessness was operated on plants. Other experiments were concerned with the breeding and formation of crystals in microgravity. In the module and on the outer wall continued were a telescope, a spectrometer and photographic equipment and other equipment for astrophysical observations.


Crystal played a major role in the cooperation of the American and Russian space program. For the first time since the Apollo - Soyuz mission carried out on crystal hitherto unique coupling of spacecraft from different nations. Furthermore, for the first time, spacecraft large mass were coupled to each other and a record weight for space complexes (the first Shuttle -Mir mission around 220, more later tonnes) achieved. In addition, for the first time crews met up to 13 people in a space station. In this framework, the technology for international missions has been substantially modified and made the nations mutually available. So the left hand still in use today androgynous APAS - coupling system is based fundamentally on the use of the crystal module. Furthermore, the first international space station built module was created with the Crystal Expansion Module SDM. This means that important knowledge was collected and developed equipment for the operation of today's International Space Station by the crystal module as part of the Mir program. On the edge is noted that the joint space program has contributed significantly to the political approach of the participating formerly hostile nations.


  • Harland, David M.; The story of Space Station Mir, Springer- Verlag, Berlin, Heidelberg, New York 2005, ISBN 0-387-23011-4